Answer:
Length = 3 ft
Step-by-step explanation:
If the equation for perimeter is p = 2 (L+W)
You can plug in the information you already have
1) 18 = 2 (L+6)
2) Simplify by first dividing 2 by itself to cancel it out and then by 18 which would equal 9 leaving you with the equation 9 = L+6
3) Now to leave the L alone on the right you need to cancel out the 6 by subtracting 6 from itself and then from 9 which would leave you with the equation and the answer to the problem, 3 = L
