So you want to solve for x?
It would be nice if this would easily factor:
(-4x + 5)(2x +1) = 0 This will not work!
So you need to use the quadratic formula:
a = -8, b = 4, c = 5
[tex] x = \frac{-b+/- \sqrt{b^{2}-4ac} }{2a}[/tex]
x = (-4 +/- [tex] \sqrt{16-4(-8)(5)} [/tex])/2(-8)
= (-4 +/- [tex] \sqrt{16 + 160} [/tex])/-16
= (-4 +[tex] \sqrt{176} [/tex])/-16
= 1/4 - [tex] \sqrt{11} [/tex]/4