Maybe 40? i hope this helps
1. Use the FOIL method (x+9)(x+9)
First, outer, inner, last

Add your like terms

2. When you add or subtract polynomials you add or subtract the like terms and then put them in order from largest to smallest exponents.
3.

4. Since it is the perimeter, we add the 3 together.

Add the like terms together:

Put them in order of exponents

Hope this helps
So the answers 3,000 cause it said period i mean unit period
Answer:
7 ft 11 inches
Step-by-step explanation:
Convert 3 1/2 yards into 10 ft 5 inches.
Subtract 2 ft 6 inches from 10 ft 5 inches.