Answer:
(a) 59 degrees
Explanation:
The mnemonic SOH CAH TOA is intended to remind you of the relationship between sides of a right triangle and trig functions of the angles. Here, the sides adjacent and opposite the unknown angle are given, so the relevant relation is ...
Tan = Opposite/Adjacent
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The side opposite is 75, and the side adjacent is 45, so ...
tan(?) = 75/45 = 5/3
The angle is found using the inverse tangent function:
? = arctan(5/3) ≈ 59.04°
The measure of the indicated angle is about 59 degrees.
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Additional comment
A portion of a calculator is shown in the attachment. The purpose is to illustrate ...
- the calculator mode is set to degrees (lower left of display)
- the inverse tangent function is the "2ND" function of the button labeled "Tan"