Square Root — O/L Mathematics

Every time you know the area of a square and want to find the length of one side, you are taking a square root. It is how a mason works out the side of a square floor from its area, how the diagonal of a room is found from the Pythagoras theorem, and how countless science formulas are unwound. Perfect squares give neat whole-number answers; most numbers do not, and this lesson teaches you how to pin those down — first by estimation, then by an exact digit-by-digit method that needs no calculator.