I understand how to set the problem up, not sure how to come up with final answer. Example x=-3 plus or minus radical 329 divided by 2. the answer is 10.57, but how do they get that?

Hmm, that?

\frac{-3 \pm \sqrt{329}}{2}

The solutions are -10.57 and 7.57 (all to 2 dp)

Well, grab a calculator. To have the negative value, you have to take the negative sign in the plus minus sign. You find the square root of 329 (18.138... ), then press - 3 minus ANS ( -3 - 18.138... ). Divide the value you just got (-21.138... ) by two to have -10.57.

To have the other solution, do the same thing except that you use plus instead of minus in the plus minus sign. You'll get 7.57.

Hope it helped! :)