Need .
the andersons decided to fence in part of their yard to use as a garden. they bought 56 ft. of fencing, and they know they want the length to be 18 ft. if they use all of the fencing, what would the width be?

Work Shown:

L = length = 18

W = width = unknown

P = perimeter of rectangle = 56

P = L+L+W+W

P = 2L+2W

P = 2*18+2W ... plug in given length

P = 36+2W

36+2W = P

36+2W = 56 ... plug in given perimeter

36+2W-36 = 56-36 ... subtract 36 from both sides

2W = 20

2W/2 = 20/2 ... divide both sides by 2

W = 10

This rectangle is 10 ft by 18 ft.

As a check,

L+L+W+W = 18+18+10+10 = 36+20 = 56

so we get the proper perimeter

note: this assumes that there is no bit of fencing that goes to waste, there are no gaps, or there are no overlapping portions.

step-by-step explanation: