Question

The length of a rectangle is 3cm more than its width and its area is 40cm2. Find the dimensions of the rectangle.

Answer 1

Let the width = x cm

then length = (x + 3) cm

now, area of rectangular plot = 40 cm²

so, length × width = 40

⇒ x(x + 3) = 40

⇒ x² + 3x - 40 = 0

⇒ x² + 8x - 5x - 40 = 0

⇒ x(x + 8) - 5(x + 8) = 0

⇒ (x - 5) (x + 8) = 0

⇒ x = 5 or x = -8 [rejected]

so width = 5 cm

and length = 5 + 3 = 8 cm