Hi can someone do this and explain how to do it

A20? -foot ladder is placed against a vertical wall of a? building, with the bottom of the ladder standing on level ground 19 feet from the base of the building. how high up the wall does the ladder? reach?

Aconstruction worker has rope 9 m long he needs to cut it in pieces that are each 3 /5 m long how many such pieces can he cut without having any rope leftover?

Carley bought a jacket that was discounted 10% off the original price. the expression below represents the discounted price in dollars, based on x, the original price of the jacket.