Q4 of 35 Page 219

A tree breaks due to a storm and the broken part bends such that the top of the tree touches the ground making an angle having measure 30 with the ground. The distance from the foot of the tree to the point where the top touches the ground is 30 m. Find the height of the tree.

Suppose AC is the tree broken at point B such that the broken part CB takes the position BD and touches the ground at D.



AD = 30 m


∠ADB = 30⁰


In ∆DAB,





AB = 10√3


Now,





BD = 20√3


So, height of the tree AC,


= AB + BC


= AB + BD


= 10√3 + 20√3


= 30√3


= 30 × 1.73


= 51.9 m


The height of the tree is 51.9 m.


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