Answer:
Width: 5
Explanation:
Perimeter is found by adding all the sides together.
1. Multiply 31 by 2 so that you get the total length of both sides.
2. 31 x 2 = 62
3. Subtract 62 from 72 in order to get the total width of both sides.
4. 72 - 62 = 10
5. Divide 10 by 2 to get the width of one side.
6. 10 / 2 = 5
Answer: 5 is your width.