Question

The perimeter of a rectangle is 42 inches. If the width of the rectangle is 9 inches, what is the length?

A.
24 inches
B.
33 inches
C.
12 inches
D.
21 inches

Answer 1

C

Explanation:

2 x length + 2 x width = perimeter

2 x length + 2 x 9 = 42

2 x length + 18 = 42

Subtract 18 from both sides

2 x length = 24

1 length = 12

Answer 2

12 inches

Explanation:

let length be L

formula for perimeter of rectangle = 2( length + width )

2( L + 9) = 42

2L + 18 = 42

2L = 24

L = 12 inches