Answer:
See explanation
Step-by-step explanation:
Usually, I just find the quadratic formula the easiest to go, but here are some tips to tell if which you should use.
1. First see if you can get integer values for the roots to multiply to c and add to b.
This is the easiest way to solve a quadratic equation, and I always check for whether I can easily find the roots by multiply two numbers for c and adding them for b.
For instance, the Quadratic 
I can easily see that 2 and 3 are the roots here - as
and
. If you can do this and receive integer values, then great! I'd definitely stick with this.
2. See if you can complete the square
If you have a quadratic which is a perfect square, you'll be able to tell if c is a perfect square, and b is twice that number. This will be easiest. <em>Any quadratic equation can be solved by completing the square</em><em>, </em>but I personally stick to this method only if I can tell it's a perfect square quadratic.
3. Stick to the Quadratic Formula
If all else fails, go with the Quadratic formula. It's not that hard and it gets the job done. I would highly discourage going with graphing, as it takes too much time and it's quite a hassle unless you have a graphing calculator.
I really hope this helped!