Q9 of 107 Page 12

From the top of a cliff 25 m high the angle of elevation of a tower is found to be equal to the angle of depression of the foot of the tower. The height of the tower is


Here AB = 25 m is cliff and CE = (25 + x) m is tower


In Δ ADE


tan θ = …………….1


In Δ ABC


tan θ = …………….. 2


From 1 and 2



x =25 m


Total height of tower is 25 + x = 25 +25 = 50 m

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