Section 7.1
Solving Right Triangles
In this section we’ll solve right triangles, which means that you will find all
lengths and measures that were not given. You’ll use the six trigonometric
functions of an angle to do this.
Applications with Right Triangles
Example 1: Use the given angle and the given side to find x and y in the
triangle below.
y
10 ft.
x
Example 2: In ∆ MAT with right angle A, MA = 9 cm and AT = 7 cm. Find
angle M.
Example 3: An isosceles triangle has sides measuring 9 inches, 14 inches,
and 14 inches. What are the measures of its angles?
Section 7.1 – Solving Right Triangles
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Example 4: A 216 foot ladder is leaned against the side of a building. If the
ladder forms a 41° angle with the ground, how high up the side of the
building does the ladder reach?
Section 7.1 – Solving Right Triangles
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Example 5: The angle of elevation to the top of a building from a point on
the ground 125 feet away from the building is 8° . How tall is the building?
Example 6: The sonar of a navy cruiser detects a submarine that is 4000 feet
from the cruiser. The angle between the water line and the submarine id ૜૝°.
How deep is the submarine?
Section 7.1 – Solving Right Triangles
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