Square area 400m2 find the area of a rectangle with the same perimeter as the square

Square area 400m2 find the area of a rectangle with the same perimeter as the square if it is known that the length of the rectangle is 28 m

First of all, we find the side of the square by expressing it from the area formula:
S = a². Therefore, a = √S.

According to the terms of the assignment, S 400 m², a = √400 = 20 m.

The perimeter of such a figure corresponds to:
P = 4a = 4 * 20 = 80 m.

The rectangle also has the sum of all sides = 80 m, and the length = 28 m.This means its half-perimeter, since opposite measurements are equal = 40 m.
Let’s find the width:

28 + b = 40.

The second term is the difference between the sum and the first:

b = 40 – 28 = 12 m.

Let’s calculate the area:
S = a * b = 28 * 12 = 336 m².