The rectangle is 4 dm wide and 3 times longer. find the area of a square with the same perimeter as the given rectangle.

Let’s find the length of the rectangle:
1) 4 * 3 = 12 (dm) – the length of the rectangle;
The perimeter of a rectangle is the sum of all sides:
2) (4 + 12) * 2 = 32 (dm) – the perimeter of the rectangle;
Because all sides of a square are equal, and its perimeter is equal to the perimeter of the rectangle, then we find the side of the square:
3) 32: 4 = 8 (dm) – side of the square;
In a square, all sides are equal, therefore, to find the area of a square, it is necessary to square the side of the square.
4) 8 ^ 2 = 64 (dm ^ 2) – the area of the square.