A ladder 15 metres long just reaches the top of a vertical wall. If the ladder makes an angle of 60° with the wall, find the height of the wall.
Length of ladder = 15 m
The angle between the wall and the ladder = 60°
Let the height of the wall = H
In ABC C = 60°, B = 90°
We know that
A + B + C = 180° (Sum of interior angles of a triangle is 180)
A + 90 + 60 = 180°
A = 30°
In ABC
Hence the height of the wall is 7.5 m