Find the length and width of the rectangle described. The length is 12 units more than the width. The perimeter is 7 times the width.

The length is 20 units. The width is 8 units.

Step-by-step explanation:

The width is an unknown, so we will let W = the width.

The length is also an unknown, but we know the length is 12 units more than the width, so the length is L = W + 12.

The perimeter is 7 times the width. P = 7W

The perimeter is also the sum of two lengths and two widths.

P = 2L + 2W

7W = 2 (W + 12) + 2W

7W = 2W + 24 + 2w

7W = 4W + 24

3W = 24

W = 8

The width is 8 units.

L = W + 12

L = 8 + 12 = 20

The length is 20 units.