Question

A 10 meter ladder is inclined against a wall at an angle of elevation of 20°. If the top of the ladder reaches the top of the wall, how tall is the wall?

Answer 1

Wall's height = 3.42 m

Explanation:

Length of the ladder = 10 meter

Suppose height of the wall = h meter

"Please find the attached image"

One right angle triangle whose opposite side is h and hypotenuse is 10m

We use the trigonometric ratio

sin Θ =
`(opposite)/(hypotenuse)`

sin Θ =
`(h)/(10)`

sin(20) =
`(h)/(10)`

0.3420 =
`(h)/(10)`

Solve for h

h = 0.3420 * 10

h = 3.42 m

Height of the wall is 3.42 m