Determine the point(s) on the curve that correspond to the given slope of the tangent.

y = (2x-1)(-4+x^2), m=3

y' = 6x^2 - 2x - 8

Set y' = 3

3 = 6x^2 - 2x - 8

0 = 6x^2 - 2x - 5

Now what do I do. I used the quadratic formula to get x-intercepts:

[2+- sqrt(124)]/12

But these do not end up being the correct x values for the two points on this function??

Can someone help me, thanks.