Question 154022
Let x be the length of the sides of the square.

The dimensions of the newly formed rectangle are as follows:
Width: x-2
Length: x+8
So the perimeter is 2(x-2)+2(x+8).
As the perimeter is given as 40, we have
2(x-2)+2(x+8)=40
Solving for x, we obtain:
2x - 4 + 2x + 16 = 40
4x + 12 = 40
4x = 28
x = 7
So the length of the side of the square is 7 cm.