Question

The perimeter of a rectangle is 48cm. its length is 4 cm. what is its width?

Answer 1

Answer:

$perimeter = 2(length + width) \\ 48 = 2(4 + w) \\ 24 = 8 + w \\ w = 16 \: cm$

Answer 2

Answer:

P = 48

4 + 4(two given lengths) = 8

48(perimeter) - 8(length of two given lengths) = 40(length of two unknown sides)

40(length of two unknown lengths) divided by 2(two missing sides) = 20 cm