An observer 1.6 m tall is 20√3 away from a tower. The angle of elevation from his eye to the top of the tower is 30°. The heights of the tower is:

Given

• Observer's eye height = 1.6 m.
• Horizontal distance to tower = 20√3 m.
• Angle of elevation = 30°.

Compute tower height Htan 30° = (H − 1.6) / (20√3) = 1/√3⇒ H − 1.6 = 20 ⇒ H = 21.6 m