Question 259951
Hello, 
We know the perimeter of a square is 4 times a side--right? OK, let's have x represent the side. Therefore we can set up an equation like this:
4x=40 Divide each side by 4 to give us:
x=10 
Therefore we know the sides are 10 inches long.
Now we can multiply each side to get the area of the top. 
10*10=100 square inches is the area. 
RJ 
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