benjamin rodz: if the area of a square is 25m2 what is the length of one side
So, a square have the same side lenght.
With this information, you can conclude to this: If 1 X 1 = 1m
2, 2 X 2 = 4m
2, so if you have the answer you can use the square root of your number...
sqrt(25)
+142 
