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Question
A ladder 15 m long just reaches the top of a vertical wall. If the ladder makes an angle of 60° with the wall, then the height of the wall is
Options
\[15\sqrt{3}m\]
\[\frac{15\sqrt{3}}{2}m\]
\[\frac{15}{2}\]
15 m
Solution
Suppose AB is the wall and AC is the ladder.
It is given that, AC = 15 m and \[\angle\]CAB = 60°.
In right ∆ABC,
\[ \Rightarrow \frac{1}{2} = \frac{AB}{15}\]
\[ \Rightarrow AB = \frac{15}{2} m\]
Thus, the height of the wall is \[\frac{15}{2}\]
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