One side of a square is reduced by 1 / 5, and the other side is increased by 2 meters to get a rectangle. The area of the rectangle is the same as that of the square

One side of a square is reduced by 1 / 5, and the other side is increased by 2 meters to get a rectangle. The area of the rectangle is the same as that of the square

I've done the type of LZ, the following should be "the area of this rectangle is equal to that of the square, find the side length (or area) of the original square."
Suppose that the side length of a square is X,
x×(1-1/5)×(x＋2)=x×x
4/5x×x+4/5x×2=x×x
4/5x×x+8/5x=x×x
(offset x at the same time)
4/5x+8/5=x
8/5=1/5x
x=8/5÷1/5
x=8/5×5
x=8
That is to say, the side length of the square is 8 and the area is 64