Answer:
h = 19.6 ft
Step-by-step explanation:
Given that,
A 20 ft ladder 4ft from the base of the wall.
The height of the ladder, H = 20 ft
The base distance, b = 4 ft
We need to find the height of the reach. Let it is P.
Using Pythagoras theorem,
or
P = 19.6 ft
So, the height is 19.6 ft.