Sheila is climbing on a ladder that is attached against the side of a jungle gym wall. she is 5 feet off the ground and 3 feet horizontally from the base of the ladder, which is 15 feet from the wall. how high up the wall is the top of the ladder?

Given:
Sheila - 5 feet off the ground, 3 feet horizontally form the base of the ladder.

ladder - 15 feet from the wall. 
Find how high up the wall the top of the ladder is.

5 : 3 = x : 15
5*15 = 3x
75 = 3x
75/3 = 3x/3
25 = x

The top of the ladder is 25 feet high.