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Mathematics LibreTexts

13.4: Right Triangle Trigonometry

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Learning Objectives

  • Use right triangles to evaluate trigonometric functions.
  • Find function values for 30°(\(\dfrac{\pi}{6}\)),45°(\(\dfrac{\pi}{4}\)),and 60°(\(\dfrac{\pi}{3}\)).
  • Use equal cofunctions of complementary angles.
  • Use the definitions of trigonometric functions of any angle.
  • Use right-triangle trigonometry to solve applied problems.

Mt. Everest, which straddles the border between China and Nepal, is the tallest mountain in the world. Measuring its height is no easy task and, in fact, the actual measurement has been a source of controversy for hundreds of years. The measurement process involves the use of triangles and a branch of mathematics known as trigonometry. In this section, we will define a new group of functions known as trigonometric functions, and find out how they can be used to measure heights, such as those of the tallest mountains.

We have previously defined the sine and cosine of an angle in terms of the coordinates of a point on the unit circle intersected by the terminal side of the angle:

\[ \begin{align*} \cos t &= x \\ \sin t &=y \end{align*} \]

In this section, we will see another way to define trigonometric functions using properties of right triangles .

Using Right Triangles to Evaluate Trigonometric Functions

In earlier sections, we used a unit circle to define the trigonometric functions . In this section, we will extend those definitions so that we can apply them to right triangles. The value of the sine or cosine function of \(t\) is its value at \(t\) radians. First, we need to create our right triangle. Figure \(\PageIndex{1}\) shows a point on a unit circle of radius 1. If we drop a vertical line segment from the point \((x,y)\) to the x -axis, we have a right triangle whose vertical side has length \(y\) and whose horizontal side has length \(x\). We can use this right triangle to redefine sine, cosine, and the other trigonometric functions as ratios of the sides of a right triangle.

Graph of quarter circle with radius of 1. Inscribed triangle with an angle of t. Point of (x,y) is at intersection of terminal side of angle and edge of circle.

\[ \cos t= \frac{x}{1}=x \]

Likewise, we know

\[ \sin t= \frac{y}{1}=y \]

These ratios still apply to the sides of a right triangle when no unit circle is involved and when the triangle is not in standard position and is not being graphed using \((x,y)\) coordinates. To be able to use these ratios freely, we will give the sides more general names: Instead of \(x\),we will call the side between the given angle and the right angle the adjacent side to angle \(t\). (Adjacent means “next to.”) Instead of \(y\),we will call the side most distant from the given angle the opposite side from angle \(t\). And instead of \(1\),we will call the side of a right triangle opposite the right angle the hypotenuse . These sides are labeled in Figure \(\PageIndex{2}\).

A right triangle with hypotenuse, opposite, and adjacent sides labeled.

Understanding Right Triangle Relationships

Given a right triangle with an acute angle of \(t\),

\[\begin{align} \sin (t) &= \dfrac{\text{opposite}}{\text{hypotenuse}} \label{sindef}\\ \cos (t) &= \dfrac{\text{adjacent}}{\text{hypotenuse}} \label{cosdef}\\ \tan (t) &= \dfrac{\text{opposite}}{\text{adjacent}} \label{tandef}\end{align}\]

A common mnemonic for remembering these relationships is SohCahToa, formed from the first letters of “ S ine is o pposite over h ypotenuse, C osine is a djacent over h ypotenuse, T angent is o pposite over a djacent.”

how to: Given the side lengths of a right triangle and one of the acute angles, find the sine, cosine, and tangent of that angle

  • Find the sine as the ratio of the opposite side to the hypotenuse.
  • Find the cosine as the ratio of the adjacent side to the hypotenuse.
  • Find the tangent is the ratio of the opposite side to the adjacent side.

Example \(\PageIndex{1}\): Evaluating a Trigonometric Function of a Right Triangle

Given the triangle shown in Figure \(\PageIndex{3}\), find the value of \(\cos α\).

A right triangle with side lengths of 8, 15, and 17. Angle alpha also labeled which is opposite to the side labeled 8.

The side adjacent to the angle is 15, and the hypotenuse of the triangle is 17, so via Equation \ref{cosdef}:

\[\begin{align*} \cos (α) &= \dfrac{\text{adjacent}}{\text{hypotenuse}} \\[4pt] &= \dfrac{15}{17} \end{align*}\]

Exercise \(\PageIndex{1}\)

Given the triangle shown in Figure \(\PageIndex{4}\), find the value of \(\sin t\).

A right triangle with sides of 7, 24, and 25. Also labeled is angle t which is opposite the side labeled 7.

\(\frac{7}{25}\)

Relating Angles and Their Functions

When working with right triangles, the same rules apply regardless of the orientation of the triangle. In fact, we can evaluate the six trigonometric functions of either of the two acute angles in the triangle in Figure \(\PageIndex{5}\). The side opposite one acute angle is the side adjacent to the other acute angle, and vice versa.

Right triangle with angles alpha and beta. Sides are labeled hypotenuse, adjacent to alpha/opposite to beta, and adjacent to beta/opposite alpha.

We will be asked to find all six trigonometric functions for a given angle in a triangle. Our strategy is to find the sine, cosine, and tangent of the angles first. Then, we can find the other trigonometric functions easily because we know that the reciprocal of sine is cosecant, the reciprocal of cosine is secant, and the reciprocal of tangent is cotangent.

how to: Given the side lengths of a right triangle, evaluate the six trigonometric functions of one of the acute angles

  • If needed, draw the right triangle and label the angle provided.
  • Identify the angle, the adjacent side, the side opposite the angle, and the hypotenuse of the right triangle.
  • sine as the ratio of the opposite side to the hypotenuse
  • cosine as the ratio of the adjacent side to the hypotenuse
  • tangent as the ratio of the opposite side to the adjacent side
  • secant as the ratio of the hypotenuse to the adjacent side
  • cosecant as the ratio of the hypotenuse to the opposite side
  • cotangent as the ratio of the adjacent side to the opposite side

Example \(\PageIndex{2}\): Evaluating Trigonometric Functions of Angles Not in Standard Position

Using the triangle shown in Figure \(\PageIndex{6}\), evaluate \( \sin α, \cos α, \tan α, \sec α, \csc α,\) and \( \cot α\).

Right triangle with sides of 3, 4, and 5. Angle alpha is also labeled which is opposite the side labeled 4.

\[ \begin{align*} \sin α &= \dfrac{\text{opposite } α}{\text{hypotenuse}} = \dfrac{4}{5} \\ \cos α &= \dfrac{\text{adjacent to }α}{\text{hypotenuse}}=\dfrac{3}{5} \\ \tan α &= \dfrac{\text{opposite }α}{\text{adjacent to }α}=\dfrac{4}{3} \\ \sec α &= \dfrac{\text{hypotenuse}}{\text{adjacent to }α}= \dfrac{5}{3} \\ \csc α &= \dfrac{\text{hypotenuse}}{\text{opposite }α}=\dfrac{5}{4} \\ \cot α &= \dfrac{\text{adjacent to }α}{\text{opposite }α}=\dfrac{3}{4} \end{align*}\]

Exercise \(\PageIndex{2}\)

Using the triangle shown in Figure \(\PageIndex{7}\), evaluate \( \sin t, \cos t,\tan t, \sec t, \csc t,\) and \(\cot t\).

Right triangle with sides 33, 56, and 65. Angle t is also labeled which is opposite to the side labeled 33.

\[\begin{align*} \sin t &= \frac{33}{65}, \cos t= \frac{56}{65},\tan t= \frac{33}{56}, \\ \\ \sec t &= \frac{65}{56},\csc t= \frac{65}{33},\cot t= \frac{56}{33} \end{align*}\]

Finding Trigonometric Functions of Special Angles Using Side Lengths

We have already discussed the trigonometric functions as they relate to the special angles on the unit circle. Now, we can use those relationships to evaluate triangles that contain those special angles. We do this because when we evaluate the special angles in trigonometric functions, they have relatively friendly values, values that contain either no or just one square root in the ratio. Therefore, these are the angles often used in math and science problems. We will use multiples of \(30°, 60°,\) and \(45°\), however, remember that when dealing with right triangles, we are limited to angles between \(0° \text{ and } 90°\).

Suppose we have a \(30°,60°,90°\) triangle, which can also be described as a \(\frac{π}{6}, \frac{π}{3},\frac{π}{2}\) triangle. The sides have lengths in the relation \(s,\sqrt{3}s,2s.\) The sides of a \(45°,45°,90° \)triangle, which can also be described as a \(\frac{π}{4},\frac{π}{4},\frac{π}{2}\) triangle, have lengths in the relation \(s,s,\sqrt{2}s.\) These relations are shown in Figure \(\PageIndex{8}\).

Two side-by-side graphs of circles with inscribed angles. First circle has angle of pi/3 inscribed, radius of 2s, base of length s and height of length . Second circle has angle of pi/4 inscribed with radius , base of length s and height of length s.

We can then use the ratios of the side lengths to evaluate trigonometric functions of special angles.

Given trigonometric functions of a special angle, evaluate using side lengths.

  • Use the side lengths shown in Figure \(\PageIndex{8}\) for the special angle you wish to evaluate.
  • Use the ratio of side lengths appropriate to the function you wish to evaluate.

Example \(\PageIndex{3}\): Evaluating Trigonometric Functions of Special Angles Using Side Lengths

Find the exact value of the trigonometric functions of \(\frac{π}{3}\), using side lengths.

\[\begin{align*} \sin (\dfrac{π}{3}) &= \dfrac{\text{opp}}{\text{hyp}}=\dfrac{\sqrt{3}s}{2s}=\dfrac{\sqrt{3}}{2} \\ \cos (\dfrac{π}{3}) &= \dfrac{\text{adj}}{\text{hyp}}=\dfrac{s}{2s}=\dfrac{1}{2} \\ \tan (\dfrac{π}{3}) &= \dfrac{\text{opp}}{\text{adj}} =\dfrac{\sqrt{3}s}{s}=\sqrt{3} \\ \sec (\dfrac{π}{3}) &= \dfrac{\text{hyp}}{\text{adj}} = \dfrac{2s}{s}=2 \\ \csc (\dfrac{π}{3}) &= \dfrac{\text{hyp}}{\text{opp}} =\dfrac{2s}{\sqrt{3}s}=\dfrac{2}{\sqrt{3}}=\dfrac{2\sqrt{3}}{3} \\ \cot (\dfrac{π}{3}) &= \dfrac{\text{adj}}{\text{opp}}=\dfrac{s}{\sqrt{3}s}=\dfrac{1}{\sqrt{3}}=\dfrac{\sqrt{3}}{3} \end{align*}\]

Exercise \(\PageIndex{3}\)

Find the exact value of the trigonometric functions of \(\frac{π}{4}\) using side lengths.

\( \sin (\frac{π}{4})=\frac{\sqrt{2}}{2}, \cos (\frac{π}{4})=\frac{\sqrt{2}}{2}, \tan (\frac{π}{4})=1,\)

\( \sec (\frac{π}{4})=\sqrt{2}, \csc (\frac{π}{4})=\sqrt{2}, \cot (\frac{π}{4}) =1 \)

Using Equal Cofunction of Complements

If we look more closely at the relationship between the sine and cosine of the special angles relative to the unit circle, we will notice a pattern. In a right triangle with angles of \(\frac{π}{6}\) and \(\frac{π}{3}\), we see that the sine of \(\frac{π}{3}\), namely \(\frac{\sqrt{3}}{2}\), is also the cosine of \(\frac{π}{6}\), while the sine of \(\frac{π}{6}\), namely \(\frac{1}{2},\) is also the cosine of \(\frac{π}{3}\) (Figure \(\PageIndex{9}\)).

\[\begin{align*} \sin \frac{π}{3} &= \cos \frac{π}{6}=\frac{\sqrt{3}s}{2s}=\frac{\sqrt{3}}{2} \\ \sin \frac{π}{6} &= \cos \frac{π}{3}=\frac{s}{2s}=\frac{1}{2} \end{align*}\]

A graph of circle with angle pi/3 inscribed with a radius of 2s, a base with length s and a height of.

This result should not be surprising because, as we see from Figure \(\PageIndex{9}\), the side opposite the angle of \(\frac{π}{3}\) is also the side adjacent to \(\frac{π}{6}\), so \(\sin (\frac{π}{3})\) and \(\cos (\frac{π}{6})\) are exactly the same ratio of the same two sides, \(\sqrt{3} s\) and \(2s.\) Similarly, \( \cos (\frac{π}{3})\) and \( \sin (\frac{π}{6})\) are also the same ratio using the same two sides, \(s\) and \(2s\).

The interrelationship between the sines and cosines of \(\frac{π}{6}\) and \(\frac{π}{3}\) also holds for the two acute angles in any right triangle, since in every case, the ratio of the same two sides would constitute the sine of one angle and the cosine of the other. Since the three angles of a triangle add to π, π,and the right angle is \(\frac{π}{2}\), the remaining two angles must also add up to \(\frac{π}{2}\). That means that a right triangle can be formed with any two angles that add to \(\frac{π}{2}\)—in other words, any two complementary angles. So we may state a cofunction identity : If any two angles are complementary, the sine of one is the cosine of the other, and vice versa. This identity is illustrated in Figure \(\PageIndex{10}\).

Right triangle with angles alpha and beta. Equivalence between sin alpha and cos beta. Equivalence between sin beta and cos alpha.

Using this identity, we can state without calculating, for instance, that the sine of \(\frac{π}{12}\) equals the cosine of \(\frac{5π}{12}\), and that the sine of \(\frac{5π}{12}\) equals the cosine of \(\frac{π}{12}\). We can also state that if, for a certain angle \(t, \cos t= \frac{5}{13},\) then \( \sin (\frac{π}{2}−t)=\frac{5}{13}\) as well.

COFUNCTION IDENTITIES

The cofunction identities in radians are listed in Table \(\PageIndex{1}\).

Table \(\PageIndex{1}\)
\( \cos t= \sin (\frac{π}{2}−t)\) \( \sin t= \cos (\dfrac{π}{2}−t)\)
\( \tan t= \cot (\dfrac{π}{2}−t) \) \( \cot t= \tan (\dfrac{π}{2}−t)\)
\( \sec t= \csc (\dfrac{π}{2}−t) \) \( \csc t= \sec (\dfrac{π}{2}−t)\)

how to: Given the sine and cosine of an angle, find the sine or cosine of its complement.

  • To find the sine of the complementary angle, find the cosine of the original angle.
  • To find the cosine of the complementary angle, find the sine of the original angle.

Example \(\PageIndex{4}\): Using Cofunction Identities

If \( \sin t = \frac{5}{12},\) find \(( \cos \frac{π}{2}−t)\).

According to the cofunction identities for sine and cosine,

\[ \sin t= \cos (\dfrac{π}{2}−t). \nonumber\]

\[ \cos (\dfrac{π}{2}−t)= \dfrac{5}{12}. \nonumber\]

Exercise \(\PageIndex{4}\)

If \(\csc (\frac{π}{6})=2,\) find \( \sec (\frac{π}{3}).\)

Using Trigonometric Functions

In previous examples, we evaluated the sine and cosine in triangles where we knew all three sides. But the real power of right-triangle trigonometry emerges when we look at triangles in which we know an angle but do not know all the sides.

how to: Given a right triangle, the length of one side, and the measure of one acute angle, find the remaining sides

  • For each side, select the trigonometric function that has the unknown side as either the numerator or the denominator. The known side will in turn be the denominator or the numerator.
  • Write an equation setting the function value of the known angle equal to the ratio of the corresponding sides.
  • Using the value of the trigonometric function and the known side length, solve for the missing side length.

Example \(\PageIndex{5}\): Finding Missing Side Lengths Using Trigonometric Ratios

Find the unknown sides of the triangle in Figure \(\PageIndex{11}\).

A right triangle with sides a, c, and 7. Angle of 30 degrees is also labeled which is opposite the side labeled 7.

We know the angle and the opposite side, so we can use the tangent to find the adjacent side.

\[ \tan (30°)= \dfrac{7}{a} \nonumber\]

We rearrange to solve for \(a\).

\[\begin{align} a &=\dfrac{7}{ \tan (30°)} \\ & =12.1 \end{align} \nonumber\]

We can use the sine to find the hypotenuse.

\[ \sin (30°)= \dfrac{7}{c} \nonumber\]

Again, we rearrange to solve for \(c\).

\[\begin{align*} c &= \dfrac{7}{\sin (30°)} =14 \end{align*}\]

Exercise \(\PageIndex{5}\):

A right triangle has one angle of \(\frac{π}{3}\) and a hypotenuse of 20. Find the unknown sides and angle of the triangle.

\(\mathrm{adjacent=10; opposite=10 \sqrt{3}; }\) missing angle is \(\frac{π}{6}\)

Using Right Triangle Trigonometry to Solve Applied Problems

Right-triangle trigonometry has many practical applications. For example, the ability to compute the lengths of sides of a triangle makes it possible to find the height of a tall object without climbing to the top or having to extend a tape measure along its height. We do so by measuring a distance from the base of the object to a point on the ground some distance away, where we can look up to the top of the tall object at an angle. The angle of elevation of an object above an observer relative to the observer is the angle between the horizontal and the line from the object to the observer's eye. The right triangle this position creates has sides that represent the unknown height, the measured distance from the base, and the angled line of sight from the ground to the top of the object. Knowing the measured distance to the base of the object and the angle of the line of sight, we can use trigonometric functions to calculate the unknown height. Similarly, we can form a triangle from the top of a tall object by looking downward. The angle of depression of an object below an observer relative to the observer is the angle between the horizontal and the line from the object to the observer's eye. See Figure \(\PageIndex{12}\).

Diagram of a radio tower with line segments extending from the top and base of the tower to a point on the ground some distance away. The two lines and the tower form a right triangle. The angle near the top of the tower is the angle of depression. The angle on the ground at a distance from the tower is the angle of elevation.

how to: Given a tall object, measure its height indirectly

  • Make a sketch of the problem situation to keep track of known and unknown information.
  • Lay out a measured distance from the base of the object to a point where the top of the object is clearly visible.
  • At the other end of the measured distance, look up to the top of the object. Measure the angle the line of sight makes with the horizontal.
  • Write an equation relating the unknown height, the measured distance, and the tangent of the angle of the line of sight.
  • Solve the equation for the unknown height.

Example \(\PageIndex{6}\): Measuring a Distance Indirectly

To find the height of a tree, a person walks to a point 30 feet from the base of the tree. She measures an angle of 57° 57° between a line of sight to the top of the tree and the ground, as shown in Figure \(\PageIndex{13}\). Find the height of the tree.

A tree with angle of 57 degrees from vantage point. Vantage point is 30 feet from tree.

We know that the angle of elevation is \(57°\) and the adjacent side is 30 ft long. The opposite side is the unknown height.

The trigonometric function relating the side opposite to an angle and the side adjacent to the angle is the tangent. So we will state our information in terms of the tangent of \(57°\), letting \(h\) be the unknown height.

\[\begin{array}{cl} \tan θ = \dfrac{\text{opposite}}{\text{adjacent}} & \text{} \\ \tan (57°) = \dfrac{h}{30} & \text{Solve for }h. \\ h=30 \tan (57°) & \text{Multiply.} \\ h≈46.2 & \text{Use a calculator.} \end{array} \]

The tree is approximately 46 feet tall.

Exercise \(\PageIndex{6}\):

How long a ladder is needed to reach a windowsill 50 feet above the ground if the ladder rests against the building making an angle of \(\frac{5π}{12}\) with the ground? Round to the nearest foot.

About 52 ft

Access these online resources for additional instruction and practice with right triangle trigonometry.

  • Finding Trig Functions on Calculator
  • Finding Trig Functions Using a Right Triangle
  • Relate Trig Functions to Sides of a Right Triangle
  • Determine Six Trig Functions from a Triangle
  • Determine Length of Right Triangle Side

Visit this website for additional practice questions from Learningpod.

Key Equations

Cofunction Identities

Key Concepts

  • We can define trigonometric functions as ratios of the side lengths of a right triangle. See Example .
  • The same side lengths can be used to evaluate the trigonometric functions of either acute angle in a right triangle. See Example .
  • We can evaluate the trigonometric functions of special angles, knowing the side lengths of the triangles in which they occur. See Example .
  • Any two complementary angles could be the two acute angles of a right triangle.
  • If two angles are complementary, the cofunction identities state that the sine of one equals the cosine of the other and vice versa. See Example .
  • We can use trigonometric functions of an angle to find unknown side lengths.
  • Select the trigonometric function representing the ratio of the unknown side to the known side. See Example .
  • Right-triangle trigonometry permits the measurement of inaccessible heights and distances.
  • The unknown height or distance can be found by creating a right triangle in which the unknown height or distance is one of the sides, and another side and angle are known. See Example .

Trigonometry Worksheets

Related Pages Math Worksheets Free Printable Worksheets

There are six sets of Trigonometry worksheets:

  • Trig Ratios: Sin, Cos, Tan
  • Sin & Cos of Complementary Angles
  • Find Missing Sides
  • Find Missing Angles
  • Area of Triangle using Sine
  • Law of Sines and Cosines

Sine, Cosine, & Tangent Worksheets

In these free math worksheets, students learn how to find the trig ratios: sine, cosine, and tangent.

There are five sets of Sine, Cosine, & Tangent worksheets: Trigonometry Worksheet (Learn Adjacent, Opposite, & Hypotenuse) Trigonometric Ratios Worksheets (Sine Ratio, Cosine Ratio, Tangent Ratio)

How to find Sine, Cosine, & Tangent worksheets? In the context of trigonometry, the sides of a right triangle are often described in relation to an angle within the triangle. The common terms used are:

Hypotenuse: The side opposite the right angle. It is the longest side of the right triangle.

Opposite: The side opposite a specified angle. In other words, if you’re looking at one of the non-right angles, the side opposite that angle is called the “opposite” side.

Adjacent: The side adjacent to a specified angle. It is the side that is next to the angle but is not the hypotenuse.

Sine (sin), cosine (cos), and tangent (tan) are three fundamental trigonometric functions that describe the relationships between the sides and angles of a right triangle. These functions are widely used in mathematics and various scientific fields.

Sine (sin): In a right triangle, the sine of an angle (θ) is the ratio of the length of the side opposite the angle to the length of the hypotenuse. sin(θ)= Opposite/Hypotenuse

Cosine (cos): The cosine of an angle (θ) in a right triangle is the ratio of the length of the side adjacent to the angle to the length of the hypotenuse. cos(θ)= Adjacent/Hypotenuse

Tangent (tan): The tangent of an angle (θ) in a right triangle is the ratio of the length of the side opposite the angle to the length of the side adjacent to the angle. tan(θ)= Opposite/Adjacent

These functions are defined not only in the context of right triangles but also more broadly using the unit circle and as periodic functions. They have various applications in physics, engineering, computer science, and other fields where understanding the relationships between angles and sides is crucial.

Click on the following worksheet to get a printable pdf document. Scroll down the page for more Sine, Cosine, & Tangent Worksheets .

Trigonometry Worksheet

More Sine, Cosine, & Tangent Worksheets

Printable (Answers on the second page.) Trigonometry Worksheet #1 (Adjacent, Opposite, & Hypotenuse) Trig Ratios Worksheet #2 (Sin, Cos, Tan Ratios) Trig Ratios Worksheet #3 (Sin, Cos, Tan Ratios) Trig Ratios Worksheet #4 (Sin, Cos, Tan Ratios) Trig Ratios Worksheet #5 (Sin, Cos, Tan Ratios)

Online Trigonometry (sine, cosine, tangent) Trigonometry (sine, cosine, tangent) Trigonometry (using a calculator) Inverse Trigonometry (using a calculator) Trigonometry (find an unknown side) Trigonometry (find an unknown angle) Using Sine Using Cosine Using Tangent Using Sine, Cosine or Tangent Trigonometry Applications Problems Law of Sines or Sine Rule Law of Sines Law of Cosines or Cosine Rule Law of Cosines

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Law of Sines Worksheet

Students will practice applying the law of sines to calculate side lengths and angle measurements. This worksheet includes word problems as well as challenging bonus problems.

Example Questions

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This is a 5 part worksheet:

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  • Pictures of Law of Sines (triangles, formula and more..)
  • Law of Sines and Cosines Worksheets

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  • Word problems in math can be identified by the use of language that describes a situation or scenario. Word problems often use words and phrases which indicate that performing calculations is needed to find a solution. Additionally, word problems will often include specific information such as numbers, measurements, and units that needed to be used to solve the problem.
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  • Symbolab is the best calculator for solving a wide range of word problems, including age problems, distance problems, cost problems, investments problems, number problems, and percent problems.
  • What is an age problem?
  • An age problem is a type of word problem in math that involves calculating the age of one or more people at a specific point in time. These problems often use phrases such as 'x years ago,' 'in y years,' or 'y years later,' which indicate that the problem is related to time and age.
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  • High School Math Solutions – Systems of Equations Calculator, Elimination A system of equations is a collection of two or more equations with the same set of variables. In this blog post,...

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  1. Pod Racing Worksheet Trigonometry Answer Key

    13 4 problem solving with trigonometry answer key pdf

  2. lesson 13 4 problem solving with trigonometry

    13 4 problem solving with trigonometry answer key pdf

  3. Solving Trigonometric Equations: Strategies for Finding

    13 4 problem solving with trigonometry answer key pdf

  4. LESSON 13 4 PROBLEM SOLVING WITH TRIGONOMETRY.docx

    13 4 problem solving with trigonometry answer key pdf

  5. 11 Solving Problems With Trigonometry HW.pdf

    13 4 problem solving with trigonometry answer key pdf

  6. Trigonometry

    13 4 problem solving with trigonometry answer key pdf

VIDEO

  1. TR 10: Pythagorean Triples (Trigonometry series by Dennis F. Davis)

  2. Fsc math part 1 chapter 9 Lec 1 Introduction To Trigonometry

  3. Trigonometric Identities

  4. TR-33: Pythagorean Trig Identities (Trigonometry series by Dennis F. Davis)

  5. Lesson 13.4 Problem Solving With Trigonometry

  6. Exercise 3.4 || Question 20 || Thomas Calculus || Trigonometric Derivative

COMMENTS

  1. PDF 13.4 Problem Solving with Trigonometry

    c A. You can use any form of the area formula to find the area of a triangle, given two side lengths and the measure of the included angle. Example 1. Find the area of each triangle to the nearest tenth. A. 3.2 m 142°. 4.7 m. Let the known side lengths be a and b. Let the known angle be ∠C.

  2. PDF LESSON Problem Solving with Trigonometry 13-4 Practice and Problem

    X(−4, 5), Y(−3, 5), Z(−3, 4) _____ Follow the steps to find the area of the triangle using trigonometry. 10. Draw a line from vertex U perpendicular to the base TV at a point W. Label its length h. Write the sine of ∠T as a ratio using variables in the figure. Solve for h. Then

  3. PDF 13-4 Practice

    13-4 Practice Form K The Sine Function Use the graph at the right to fi nd or estimate the value of y 5 sin u for each value of u. 1. p radians 2. 2 radians 3. 3p 2 radians 4. 4 radians Determine the number of cycles each sine function has in the interval from 0 to 2π. Th en fi nd the period of each function. 5. 6. Find the amplitude of the ...

  4. PDF LESSON Problem Solving with Trigonometry 13-4 Practice and Problem

    find the area. For Problems 4 7, follow the steps to derive an area formula, and then apply the formula to find the areas. 4. If you know AB and the measure of A, you can find the height of the triangle. Write a trigonometric equation to relate A, h, and c. _____ 5. Solve for h. h _____ Substitute your value for h into

  5. PDF CHAPTER Solutions Key 13 Trigonometric Functions

    s top s = rtopθ rendθ = ( end rtop r end )θ = 143 ( __ π 4) ≈ 33. The length of the arc traced by the top end of the wiper blade is about 33 in. greater than the length of the arc traced by the bottom end of the wiper blade. 49. Possible answer: When P lies on the unit circle.

  6. 13.4 problem solving with trigonometry answer key

    Unlocking Trigonometry: Unveiling the Answer Key for 13.4 Problem Solving Trigonometry is a branch of mathematics that deals with the relationships between the angles and sides of triangles. It is used in a variety of fields, including physics, engineering, and architecture, to solve problems involving angles and distances.

  7. PDF Practice Questions (and Answers)

    Practice Questions (and Answers) Topics include trig values, half-angle identities, angular ... Trigonometry Concepts Review 12) 13) Solve for the interval tam- + secx = 1 180 CosB - and sinA where A a) b) 4 90 < A < 180 Sin2A Cos2B mathplane.com . 14) 15) Transform the equation by solving for

  8. Trigonometry Worksheets (pdf) with answer keys. Download print and enjoy!

    Plus each one comes with an answer key. Law of Sines and Cosines Worksheet. (This sheet is a summative worksheet that focuses on deciding when to use the law of sines or cosines as well as on using both formulas to solve for a single triangle's side or angle) Law of Sines. Ambiguous Case of the Law of Sines. Law Of Cosines.

  9. 13.4: Right Triangle Trigonometry

    Figure 13.4.9: The sine of π 3 equals the cosine of π 6 and vice versa. This result should not be surprising because, as we see from Figure 13.4.9, the side opposite the angle of π 3 is also the side adjacent to π 6, so sin( π 3) and cos( π 6) are exactly the same ratio of the same two sides, √3s and 2s.

  10. PDF Supplementary Trigonometry Exercise Problems

    4 m 16) Solve the problem. 17) For a circle of radius 4 feet, find the arc length s subtended by a central angle of 60 °. Round to the nearest hundredth. 17) 18) A pendulum swings though an angle of 30 ° each second. If the pendulum is 35 inches long, how far does its tip move each second? If necessary, r ound the answer to two decimal places ...

  11. PDF Chapter 13: Trigonometric Functions

    short answer items. TestCheck and Worksheet Builder This CD-ROM can be used to create additional unit tests and review worksheets. TTrigonometryrigonometry Trigonometry is used in navigation, physics, and construction, among other fields. In this unit, you will learn about trigonometric functions, graphs, and identities. 696 Unit 5 Trigonometry ...

  12. PDF I NAME DATE 6,-1 Practice W rksheet

    6-4 Practice Worksheet Inverse Trigonometric Functions Write each equation in the form of an inverse relation. 1. 0.75 = sinx 2. -1 = cosx 3. 0.1 = tan 0 • / 3 12 "_ 6. cos _ = --4. _ = cos x 5. sin x - 2 13 Find the values of x in the interval 0° <_x < 360° that satisfy each equation. 7. x = arccos 1 8. arccos V22 -x 9. arcsin_=x1

  13. PDF Chapter 13 Resource Masters

    ©Glencoe/McGraw-Hill iv Glencoe Algebra 2 Teacher's Guide to Using the Chapter 13 Resource Masters The Fast FileChapter Resource system allows you to conveniently file the resources you use most often. The Chapter 13 Resource Mastersincludes the core materials needed for Chapter 13.

  14. 13.4

    View 13.4 - Problem Solving with Trigonometry.pdf from MATH geometry at Alonzo And Tracy Mourning Senior High Biscayne Bay. Name: _ Period: _Date: _ Page #: _ Geometry Module 13 - Trigonometry 13.4 -

  15. Trigonometry Worksheets (worksheets, printable, online, answers)

    How to find trigonometry ratios sine, cosine, and tangent. Trig Ratios. Free Printable and Online Worksheet with answers. opposite, adjacent and hypotenuse. Practice Worksheets for Geometry and Trigonometry.

  16. PDF NAME DATE PERIOD 4-1 Practice

    Lesson 4-1 Chapter 4 7 Glencoe Precalculus Find the exact values of the six trigonometric functions of θ. 1. 3 8 θ 2. 7 24 θ Find the value of x. Round to the nearest tenth, if necessary. 3. 63.1 56° x 4. 19.2 26° x 5. On a college campus, the library is 80 yards due east of the dormitory and the recreation center is due north of the library.

  17. Trigonometry

    Now, with expert-verified solutions from Trigonometry 8th Edition, you'll learn how to solve your toughest homework problems. Our resource for Trigonometry includes answers to chapter exercises, as well as detailed information to walk you through the process step by step. With Expert Solutions for thousands of practice problems, you can take ...

  18. PDF I. Model Problems II. Practice III. Challenge Problems IV. Answer Key

    Step 3: Use SOHCAHTOA to solve for the unknown side of the right triangle: y ft y y y 42.90 36(1.19175) 36tan50 36 tan50 q q (Note that units of feet were dropped for simplicity.) Step 4: Determine the height of the building: Since Michael's eyes are six feet from the ground, we must add six feet to variable y to get h: 49 ( ) 48.90 6 42.90 6 ...

  19. PDF trig 13.1 day key

    Estimate the height of the school to the nearest foot. Solution 1. Draw a diagram that represents the situation. 2. Write and solve an equation to find the height h. tan (tan 620) = h. The height of the school is about feet. Checkpoint Complete the following exercise. 3.

  20. PDF my.hrw

    18.4 Problem Solving with Trigonometry Use a trigonometric ratio to find the distance DF. Round your answer to the nearest integer. A building casts a 30 m shadow when the Sun is at an angle of 27° to the vertical. How far is it from the top of the building to the tip of the shadow to the nearest meter?

  21. PDF LESSON Problem Solving with Trigonometry 13-4

    trigonometry to find the area. For Problems 4 7, follow the steps to derive an area formula, and then apply the formula to find the areas. 4. If you know AB and the measure of A, you can find the height of the triangle. Write a trigonometric equation to relate A, h, and c. _____ 5. Solve for h. h _____ Substitute your value for h into

  22. Law of Sines Worksheet (pdf) with answer key and model problems

    This is a 5 part worksheet: Part I Model Problems. Part II Practice Problems (1-6) Part III Practice (harder) & Word Problems (7 - 18) Part IV Challenge Problems. Part V Answer Key.

  23. PDF UNIT 12 Teacher: Per:

    In Exercises 1-4, give each answer as a fraction in terms of. p, q, and . r. 1. sin. P _____ 2. cos. P _____ 3. tan. P _____ 4. sin. ... Lesson 12.5 • Problem Solving with Trigonometry. Name Period Date. 1. While floating down a river with a 2.75 mi/h current, Alicia decides ... Geometry 1-2 Trigonometry | 13. 7. About 24° 8. About 43.0 cm

  24. Word Problems Calculator

    Try underlining or highlighting key information, such as numbers and key words that indicate what operation is needed to perform. Translate the problem into mathematical expressions or equations, and use the information and equations generated to solve for the answer.