Question

Two buildings are 12m apart on the same horizontal level. From the top of the taller building, the angle of depression of the bottom of the shorter building is 48degrees and from the bottom, the angle of of elevation of the top of the shorter building is 36 degrees. Calculate the difference in the heights of the buildings

Answer 1

2.08 meters

Explanation:

From the diagram attached :

We can calculate the height of the shorter building using trigonometry :

s = Height of shorter building

t = height of taller building

Tanθ = opposite / Adjacent

θ = 36°

Adjacent = 12, opposite = s

Tan36° = s / 12

0.7265425 × 12 = s

s = 8.72 meters

s = height of shorter building 8.72 meters ( 2 decimal places)

Height of taller building :

Tanθ = opposite / Adjacent

θ = 48°

Adjacent = t ; opposite = 12

Tan48° = 12 / t

1.1106125 = 12 / t

1.1106125 × t = 12

t = 12 / 1.1106125

t = 10.80 meters ( 2 decimal places)

Height of Taller building = 10.80 meters

Difference in height :

(10.80m - 8.72m) = 2.08 meters