Cube root of 30:
Equivalent to 30^(1/3) = <span>3.10723250595
Approximately rounded to 3.12.</span>
This is a right triangle, the measure of angle A is 90 degrees.
First thing to do I guess is finding B and C.
tan^-1 (7/12) = 30 degrees
tan^-1 (12/7) = 60 degrees
60 + 30 = 90
180 - 90 = 90. Therefore angle A = 90 degrees