Question

The breadth of a rectangle is 4 cm less than its length. If the length is increased by 4 cm and the
breadth is decreased by 1 cm, the area of the rectangle is increased by 40 cm. Find the length and
breadth of the rectangle.​

Answer 1

Answer:

20 cm and 16 cm

Step-by-step explanation:

let the length of the rectangle be x cm

then breadth = (x - 4) cm

area of the rectangle = x(x - 4)

= (x² - 4x)cm²

as per the question,

=> (x+4)(x - 4 - 1) = (x² - 4x ) + 40 cm²

=> (x+4)(x - 5) = x² - 4x + 40

=> x² - x - 20 = x² - 4x + 40

=> 3x = 60 cm

=> x. = 20 cm

length = x = 20 cm

breadth = x - 4 = 16 cm