Question

The perimeter of a rectangle is 90 feet. The length is 27 feet.

Answer 1

P= 2L + 2W
90=(27)2 +2W
90=54 + 2W
-54 -54
36=2W
÷2 ÷2
18= W

Answer 2

P = 2(l+w)

substitute in the knowns

90 = 2(27+w)

divide by 2

90/2 = 2/2 *(27+w)

45 = 27+w

subtract 27 from each side

18=w

w = 18ft