STEP 1: Determine length of all sides. There are 6 sides to this shape.
Sides: 11 in 19 in 18 in 10 in
For the last two, subtract the length of the short side, from the length of the longest side. (18 in right side - 11 in left side)= 7 in - top center down (19 in bottom - 10 in top)= 9 in - top left across