posted by Jon on .
P(-15/17,-8/17) is found on the unit circle. Find sin theta and cos theta.
P(-15/17,-8/17)= P(cos theta,sin theta)
The x side, y side and radius form a right triangle with side ratio 8:15:17
cos theta is x/r = -15/17 and sin theta is -8/17
So your answer is correct