How to do this trig question?

51.3 degrees

Step-by-step explanation:

You use the tangent function. You know that tangent of an angle, y, is opposite/adjacent. Set up an equation:

tan(y) = 10/8

You use the inverse tangent (NOT COTANGENT) function, and you get:

y = tan^-1 (10/8)

Type this in your calculator, and you get 51.3 degrees.