In each figure, there are two similar triangles. Find the unknown measurement. Give any approximation to the nearest tenth.
Ch. 1 - Trigonometric Functions
Chapter 2, Problem 23
The measures of two angles of a triangle are given. Find the measure of the third angle. See Example 2. 37° , 52°
Verified step by step guidance1
Recall that the sum of the interior angles of any triangle is always 180 degrees. This is a fundamental property of triangles.
Identify the given angles: 37° and 52°.
Set up an equation to find the third angle, which we'll call \( x \):
\[ 37 + 52 + x = 180 \]
Combine the known angles on the left side:
\[ 89 + x = 180 \]
Solve for \( x \) by subtracting 89 from both sides:
\[ x = 180 - 89 \]

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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Triangle Angle Sum Property
The sum of the interior angles of any triangle is always 180 degrees. This fundamental property allows us to find the measure of the third angle when the other two angles are known by subtracting their sum from 180°.
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Sum and Difference of Tangent
Basic Arithmetic Operations
To find the unknown angle, you need to perform simple addition and subtraction. First, add the two given angles, then subtract their sum from 180° to get the third angle's measure.
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Algebraic Operations on Vectors
Angle Measurement Units
Angles are measured in degrees (°), a unit that divides a full rotation into 360 parts. Understanding this unit is essential for interpreting and calculating angle measures correctly.
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Reference Angles on the Unit Circle
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