In triangle RST, RT = 9, ST = 15, and angle R = 120 degrees. To the nearest tenth, what is angle S?
+91 You can solve the question using the law of sines:
(sin A)/a = (sin B)/b = (sin C)/c
A, B and C are angles in the triangle; a, b, and c are the side lengths opposite to their respective angles.
Plugging this in we get:
sin(120)/15 = sin(S)/9
sin(120) = sin(S) * 5/3
sin-1{[sin(120)]/(5/3)} = S
S ≈ 31.3°
Solved! :)
