Question

Please help me with this precal problem :)

a building casts a 121.6 foot shadow when the sun is 81.7 degrees above the horizon.

how tall is the building?
and at what value of theta will the shadow be twice as long as the building?

thank you so much! God bless!

Answer 1

Explanation:

Draw a picture.

θ = 81.7°

tanθ = height/121.6

height = 121.6tanθ ≅ 833.5

The building is 833.5 ft high.

:::::

When shadow is 2×121.6 = 243.2 ft long, tanθ = height/243.2

θ = arctan(height/243.2) ≅ 73.7°