Answer:
see below
Step-by-step explanation:
You will need the hypotenuse 12 ^2 + 9^2 = h^2 h = 15
In a right triangle:
S O H C A H T O A
sin s = S A H = Opposite / Hypotenuse = 12/15
cos r = C A H = Adjacent / Hypotenuse = 12/ 15
Tan s = T O A = 12 / 9
cos (theta) = cos s = 9 / 15
Tan r = 9/12
arc cos(theta) = theta = arccos(9/15) = 53.13 degrees
