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The angle of elevation of the top of a tower from a point is 30°. When the observer moves 50 meter closer, the angle becomes 60°. Find the height of the tower.

Solution

✅ Correct Option: 1

Let the height be hh and the nearer distance be xx.

From the nearer point, tan⁡60∘=h/x\tan 60^\circ = h/x, so h=x3h = x\sqrt{3}.

From the farther point, tan⁡30∘=h/(x+50)\tan 30^\circ = h/(x+50), so h=(x+50)/3h = (x+50)/\sqrt{3}.

Equating, 3x=x+503x = x + 50, so x=25x = 25 and h=253h = 25\sqrt{3} metres.

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