Answer: a = 23 ft.
Reasoning:
The question asks for the value of the leg a, given the tangent of the opposite angle and the length of the adjacent-leg, b.
The ratio that relates the three parameters is:
tan(A) = opposite-leg / adjacent-leg = a / b = a / 23 ft
Solve for a, wich is the unknown:
a = 23ft * tan(A) = 23ft * 1.0 = 23 ft
Answer: 23 ft.
