You and a friend want to know how much rope you need to climb a large rock. To estimate the height of the rock, your friend uses a square to line up the top and the bottom of the rock, as seen in the diagram. You measure the vertical distance from the ground to your friend’s eye to be 5.5 feet and the distance from your friend to the rock to be 18 feet. The angle formed by the square is a 90 degree angle. Calculate the height of the rock.

Question

You and a friend want to know how much rope you need to climb a large rock.  To estimate the height of the rock, your friend uses a square to line up the top and the bottom of the rock, as seen in the diagram.  You measure the vertical distance from the ground to your friend’s eye to be 5.5 feet and the distance from your friend to the rock to be 18 feet. The angle formed by the square is a 90 degree angle. Calculate the height of the rock.