Find the perimeter of a rectangle if its area is 28 and one side is exactly seven times the other side.

A rectangle is a quadrilateral in which opposite sides are parallel and equal to each other, and all corners are straight:

AB = CD;

BC = AD.

The perimeter of a rectangle is the sum of all its sides:

P = AB + BC + CD + AD.

The area of ​​a rectangle is equal to the product of its length and width:

S = a * b, where:

S is the area of ​​the rectangle;

a is the length of the BC rectangle;

b – its width AB.

Since the length of the rectangle is seven times its width, and the area is 28 cm2, we express:

x is the width of the rectangle;

7x – its length;

x * 7x = 28;

7×2 = 28;

x2 = 28/7 = 4;

x = √4 = 2;

AB = 2 cm;

BC = 7 2 = 14 cm.

P = 2 + 14 + 2 + 14 = 32 cm.

Answer: The perimeter of the rectangle is 32 cm.