I used the quadratic formula after moving the 6 back over to the other side:
[tex]x= \frac{4+/- \sqrt{16-4(-2)(-6)} }{-4} [/tex]
[tex]x= \frac{4+/- \sqrt{64} }{-4} [/tex]
[tex]x= \frac{4+/-8}{-4} [/tex]
[tex]x= \frac{4+8}{-4}=-3 [/tex] and
[tex]x= \frac{4-8}{-4} =1[/tex]