The horizontal distance between two trees of different heights is 60 m. The angle of depression of the top of the first tree when seen from the top of the second tree is 45°. If the height of the second tree is 80 m, find the height of the first tree.


In the fig let CE be the height of the first tree


and AB is the height of the second tree.


In ∆ADE


tan 45° =


1 =


h = 60m


Therefore height of the first tree is 80-60 = 20m



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