The length of a rectangle is four times its breadth. If its length is increased by 20 cm. and breadth is increased by 30 cm, the area of the rectangle is increased by 880 cm². Find the length of the rectangle.
Let Breadth = x Then Length= 4x ∴ Original area = 4x × x = 4x2 Now, New Area = (4x+20) (x+30) According to Question, => (4x+20) (x+30) - 4x2= 880 => 4x2+ 140x + 600 - 4x2= 880 => x = 2 Length = 8cm