Square Roots Using a Factor Tree

The square root of 18 is not a perfect square but there is a simplified way of writing this.First you need to do a prime factorization of the number 18 which looks like the image to the left. Once you have the prime factors of 2, 3 and 3 you put two times three times three in the square root.

Any pair of numbers makes that number appear on the outside of the square root making it look like this.

Which is the simplified way of writing the square root of 18.