Hi all, I have been thinking long and hard and trying to rationalize the reason for squaring an equation. I still don't understand why we do it. It's mainly in physics that I don't get it. I understand full well and accept that to get the area of a circle you multiply pi by r^2. But why do you have to to square the r? Is it because you have to take into account both the length and width of the circle? If this is true, then why do we square T in the following equation? What does a squared T (period) represent? The period can't represent length and width so then what does it? T2 * g / (4 pi) = L The previous equation was rearranged from: T = 2 pi * square root(L/g) Any help trying to untangle my thinking would be great.