Question

A ladder 15 metres long just reaches the top of a vertical wall. If the ladder makes an angle of ${60}^{\circ }$ with the wall, find the height of the wall.

Answer 1

Let hieght of the wall be x m
angle of elevation = 60^o
and,
height of the ladder (hyptoenuse) = 15 m
Now,

$sin60=\frac{oppositeside}{hypotenuse}$

$\frac{\sqrt{3}}{2}=\frac{x}{15}$

$x=\frac{15\sqrt{3}}{2}$

Therefore hieght of the wall is $\frac{15\sqrt{3}}{2}$