How do you factor #x^2+8=-6x#?
Move the -6x over to the left side.
You have: x^2 + 6x + 8
Our leading factor is one, so we don't need any extra steps.
Thus, we need to two factors that multiplies to 8 and adds 6.
If you think about it, 4+2 = 6 and 4 * 2 = 8, so we can pick out 4 and 2.
The factored form of this equation is (x+4) (x+2) = 0
NOTE: Practice some more of these things since they will be handy for finding x-intercepts in the future. You can also check this answer and verify using your calculator and putting into slope-intercept form.
Hope this helped!