A boy 1.4 m tall, stood 10m away from a tree of height 12 m. Calculate, correct to the nearest degree, the angle of elevation of the top of the tree from the boy’s eyes.
- 70º
-
47º
- 19º
- 8º
The correct answer is: B
Explanation
The angle of elevation
= Tan θ = \(\frac{opp}{adj}\)
Tan θ = \(\frac{12- 1.4}{10}\)
Tan θ = \(\frac{10.6}{10}\)
θ = Tan\(^{-1}\)(1.06)
θ ≈ 47º