Right angle Trigonometry, please help me solve (find the angle ) and explain!

Answer:
<A = 41.41
Step-by-step explanation:
You want angle A. Call it theta.
AC is the adjacent side. It is the side that is NOT the Hypotenuse.
The Hypotenuses is the longest side in a right triangle.
Cos-1 (Adjacent Side / Hypotenuse ) = theta
Adjacent side = 6
Hypotenuse = 8
Cos-1(6 / 8) = theta
theta = Cos-1(0.75)
theta = 41.41 rounded.