This simply means that the square root of the product of 2 numbers is equal to the products of their individual square roots, an example may serve to make this clear and I will choose a very simple example where a and b are both equal to 4.

We do not need to go any further to see that the square root of 16 is indeed the same as 2×2, of course being the number 4. If we try a slightly more complicated example we should arrive at the same type of result:

I have chosen these numbers purely because I know off the top of my head what the results are, the square root of 400 is 20 and the square root of 625 is 25. 20×25 is 500 so therefore the product 400×625 should be equal to 500 squared. 

500 squared is 250,000, and 400×625 is 250,000 so once again the rule has proven itself to be accurate.


Back To >> Solving Quadratics by Completing the Square (S) <<