A 20 ft ladder leans against a building. Let x represent the distance between the building and

Question:

A 20 ft ladder leans against a building. Let x represent the distance between the building and the foot of the ladder, and let y represent the height the ladder reaches on the building.
a. Write an equation for y in terms of x.
b. Find the height the ladder reaches on the building if the foot of the ladder is 10 ft from the building.
c. Find the distance of the foot of the ladder from the building if the ladder must reach 18 ft up the wall.