Question

Given a right △ABC, where AB = 4.5 cm, BC = 7.794 cm, and AC = 9 cm, sketch the triangle below, and find the measure m∠C in degrees, rounded to the nearest tenth, if necessary.

Answer 1

30°

Explanation:

The ratio of the side opposite (AB) to the hypotenuse (AC) is ...

4.5/9 = 1/2

From your memory of a short table of trig functions you know this is the sine of 30°. From the mnemonic SOH CAH TOA, you know that

Sin = Opposite/Hypotenuse

Putting these facts together gets you ...

sin(C) = 1/2 = sin(30°)

C = 30°