Look at the figure below.
An irregular shape is made of 2 rectangles. The lower rectangle is 8 feet long and 1 foot wide. Centered on top of it is another rectangle that is 2 feet wide and an unknown length. The top rectangle is 1 foot shorter in length than the lower rectangle on both sides. The 2 rectangles form 1 shape.
Part A
Find the length of the missing side. Enter your answer in the box.
The missing side is
feet.