This is a right triangle, so we can use trig functions
We know that tan theta = opp side/ adj side
tan A = CB/ AC
tan A = 8/4
Taking the inverse tan of each side
tan ^-1 ( tan A) = tan ^-1 ( 2)
Using the inverse tan button on your calculator
tan ^ -1 (2)
A = 63.43494
Rounding to the nearest thousandth
A = 63.435
