1. The perimeter of a rectangle is 78 cm. The length is 3 greater than twice its width. Find the dimensions.

2.

P=2 (L+W)

P=78

L=3+2W

78=2 (L+W)

divide both sides by 2

39=L+W

sub 3+2W for L

39=3+2W+W

39=3+3W

minus 3 both sides

36=3W

divide both sides by 3

12=W

width=12

sub back to find length

L=3+2W

L=3+2 (12)

L=3+24

L=27

it is 12 by 27