Trigonometric ratios in right triangles. Set up an equation based on the ratio you chose in the step 1. To find missing angles and sides if you know any 3 of the sides or angles.
Sine Cosine and Tangent.
Locate the two sides that you use in the trig ratio. Divide the measure of the opposite side of your angle by the measure of your hypotenuse. Because you are finding the sine of. Exactly the same idea but different side ratios.