If the length of a rectangle is three more than twice its width and its perimeter is 24 cm, what are the dimensions of the rectangle? [Page No. 21]

Let width be w cm. Then, length = (2w + 3) cm.

Perimeter = 2(length + width)

$$24 = 2[(2w + 3) + w]$$

$$24 = 2(3w + 3)$$

$$24 = 6w + 6$$

$$\Rightarrow 6w = 18$$

$$\Rightarrow w = 3.$$

Hence, width = 3 cm and length = 2(3) + 3

$$= 9 \text{ cm.}$$