Find the missing coordinate of P, using the fact that P lies on the unit circle in the given quadrant.

a) P( ,-15/17) Quadrant IV

b) P(2/5, ) Quadrant I

1 answer

the unit circle has a radius of 1 ... x^2 + y^2 = 1^2

a) x^2 = 1 - (225 / 289) = 64 / 289 ... x = 8 / 17

b) y^2 = 1 - (4 / 25) = 21 / 25