Question

A rectangle has a length 2 cm larger than its width.

(a) If the perimeter of the rectangle is 14 cm, what are the dimensions of the rectangle?

Answer 1

The width is 5/2 = 2.5 cm

The length is 9/2 = 4.5cm

Explanation:

The length is 2 longer than the width

l = w+2

The perimeter is 14

P =2 ( l+w)

14 = 2 (l+w)

Replace l with w+2

14 = 2 ( w+2+w)

14 =2 (2w+2)

Divide each side by 2

14/2 = 2/2(2w+2)

7 = 2w+2

Subtract 2

7-2 = 2w+2-2

5 = 2w

Divide by 2

5/2 = w

The length is w+2

5/2+2

5/2+4/2 = 9/2

The width is 5/2 = 2.5

The length is 9/2 = 4.5