Answer:
about 102 feet
Step-by-step explanation:
From the definition of the cotangent function, we can write ...
h·cot(α1) = d1
h·cot(α2) = d2
Where h is the building height and (α1, d1), (α2, d2) are (elevation angle, distance from the building) for the two cases.
We have d2 - d1 = 10 ft, so ...
h(cot(68°) -cot(73°)) = 10 ft
h = (10 ft)/(cot(68°) -cot(73°)) ≈ (10 ft)/(0.404026 -0.305731) ≈ 101.73 ft
The building is about 102 feet tall.
