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TF is a tower with F on the ground. The angle of elevation of T from A is x° such that tan x° = (2 / 5) and AF = 200m. The angle of elevation of T from a nearer point B is y° with BF = 80m. The value of y° is
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- 60°
- 30°
- 75°
- 45°
Correct Option: D
TF = Tower = h metre
∠TAF = x° ; ∠TBF = y°,
BF = 80 metre
In ∆AFT,
| tan x° = | AF |
| ⇒ | = | 5 | 200 |
| ⇒ h = | × 200 | 5 |
= 80 metre
In ∆BFT
| tan y° = | FB |
| ⇒ tan y° = | = 1 | 80 |
⇒ tan y° = tan 45°
⇒ y = 45°
