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Question
A ladder 15 m long makes an angle of 60° with the wall. Find the height of the point where the ladder touches the wall.
Solution
AC = 15 m is the ladder. Let AB = h be the height.
\[In \bigtriangleup ABC, \]
\[\sin60^o = \frac{AB}{AC} = \frac{h}{15}\]
\[ \Rightarrow \frac{\sqrt{3}}{2} = \frac{h}{15}\]
\[ \Rightarrow h = \frac{15\sqrt{3}}{2}\]
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