We have a right triangle and an indicated angle of 59°. Opposite that angle is the height of the building, which we seek. Adjacent to that angle is the distance to the building, which we know is 63 feet.
We have a problem with opposite and adjacent so we use the tangent function.
tan 59° = h / 63
h = 63 tan 59° ≈ 104.8496074
Answer: 105 feet
