Question

What is the value of tan A? I'm confused

Answer 1

Tanθ=(length of opposite side)/(length of side adjacent to the angle)

tanθ=12/9 *15 is the hypotenuse of the triangle. Don't use this for tan!

θ=53.13°
I am assuming you don't need this in radians?

Answer 2

tan(A) = Opp/Adj = CB / AC = 12/9 = 4/3

hope it helps