The plus sign is a composite of rectangles . The shape is comprised of:
1. 4 congruent rectangles with sides 20 in and 12 in
2. A square at the center with sides 20 in by 20in
The total area of Demi's Tester ca be found using the formula:
Substituting the given side lengths:
Hence, the total area of Demi's poster is 1360 square in