How to factorise
x^2-9

Step-by-step explanation:

This equation is called a "difference in perfect squares".

The resulting answer should be: where the y variable is the square root of the given number. In this instance, the integer 9

So knowing that the square root of 9 is 3 we can plug in 3 for both of the y spots which results in our answer.

If you wish to check this answer you can peform the "FOIL" method (first, outside, inside, last) in order to solve the equation which would result in:

I hope this helped! Feel free to ask questions if needed!