Question

∠A is an acute angle in a right triangle.

Given that cos A=15/17, what is the ratio for sin A?

Answer 1

cosine = adjacent / hypotenuse

So that means the adjacent side = 15 and the hypotenuse = 17

By Pythagorean Theorem, we know that

opposite^2 = hypotenuse^2 - adjacent^2

opposite^2 = 17^2 - 15^2

opposite^2 = 289 - 225

opposite^2 = 64

opposite side = 8

sine = opposite / hypotenuse

So,

sine A = 8 / 17