Question

The length of a rectangle is 20m more than its width. If the perimeter of the rectangle is 100m, then find the length and breadth of rectangle.

Answer 1

Let the width of a rectangle (b) = x m 

Then the length of a rectangle (l) 

= 20 more than its width 

= (x + 20) m 

Perimeter of the rectangle = 100 m 

⇒ 2(1 + b) = 100 

⇒ 2(x + 20 + x) = 100 

⇒ 2(2x + 20) = 100 

⇒ 4x + 40 = 100 

⇒ 4x + 40 – 40 = 100 – 40 (Subtract 40 on both sides) 

⇒ 4x = 60 4x 60

⇒ 4x/4 = 60/2 (Divide by 4 on both sides) 

⇒ x = 15 m 

∴ Width x = 15 m 

Length = x + 20 = 15 + 20 = 35 m