Question

The terminal side of θ passes through the point (−9,10). What is the exact value of sinθ in simplified form?

Answer 1

sin(θ) is equal to the ratio of the y-coordinate to the distance between the point (-9, 10) and the origin.

The distance is

√((-9)² + 10²) = √(81 + 100) = √181

and so

sin(θ) = 10/√181