Answer:
The length of the other side should be larger than 6cm so that the area of the rectangle is greater than the perimeter of a square with a side of 6 cm.
Step-by-step explanation:
The perimeter of a square with a side of s cm is given by the following formula:

So, with a side of 6 cm, we have that;
cm
The area of a rectangle, with width w and length l is given by the following formula

In this problem, we have that:
The width of a rectangle is 4 cm. This means that 
What should the length of the other side be so that the area of the rectangle is greater than the perimeter of a square with a side of 6 cm?
We want to have:

So



The length of the other side should be larger than 6cm so that the area of the rectangle is greater than the perimeter of a square with a side of 6 cm.