Question

Given the following triangle, if c = 17 and a = 15, find the measure of A. 28° 41° 62°

Answer 1

I'm not sure if it's a right triangle, but if not then you can use side-angle-side (SAS). No wait we don't have an angle, so it must be a right triangle (has a 90° angle).
Using trig, a is the side opposite A, and c is the hypotenuse.
Therefore using SOH-CAH-TOA, sin < = O/H = opposite/hypotenuse:
So sin A = 15/17 = 0.882

`So \: arcsin \: ( {sin}^( - 1) ) \: of \: 0.882 \: = a`
A = 61.92° = 62°