Question

Given the triangle below, what is m 2A, rounded to the nearest tenth?

B
18
11
309
A
C
Triangle not drawn to scale
A. 17.8
OB. 20.4
O C. 24.2
D. 26.8

Answer 1

9514 1404 393

Answer:

A. 17.8°

Explanation:

We have an angle and an opposite side, so we can use the law of sines to find the angle of interest.

sin(A)/a = sin(C)/c

A = arcsin(a/c·sin(C)) = arcsin(11/18·1/2) = arcsin(11/36)

A ≈ 17.7916° ≈ 17.8°