A rectangle has perimeter 78 cm and length 32 cm. What is its width?

width = 7 cm

Step-by-step explanation:

So, to find the perimeter you multiply the width by 2, multiply the length by 2, then add them together.

P = 2L + 2W

But, we already know the perimeter and length, so we need to find the width.

78 = 2 (32) + 2W

78 = 64 + 2W

-64 - 64

14 = 2W

/2 / 2

7 = W

So, to check your answer, plug in the width (that you just found), and the length to see if you get 78, the perimeter.

P = 2L + 2W

P = 2 (32) + 2 (7)

P = 64 + 14

P = 78

So, yes, the width = 7