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Question
A person is standing at a distance of 80 m from a church looking at its top. The angle of elevation is of 45°. Find the height of the church.
Solution
Let AB be the church and C be the position of the person from the church.
Suppose the height of the church be h m. 
In right ∆ABC,
\[\tan45^\circ = \frac{AB}{BC}\]
\[ \Rightarrow 1 = \frac{h}{80}\]
\[ \Rightarrow h = 80\] m
Thus, the height of the church is 80 m.
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