Based on Figure 9.3.29.3.2\PageIndex{2}, we see that the hypotenuse equals 555, so sinθ=35sinθ=35\sin θ=35, sin θ=35sin θ=35\sin θ=35, and cosθ=−45cosθ=−45\cos θ=−45.
I believe there is a divisor missing therefore based on the triangle sin(x) = 3/5 opposite over hypotenuse and cos(x) = -4/5 adjacent over hypotenuse