1. ## Inequality

I have an inequality and I don't know if I need to use the quadratic formula or not...it's like this:

x^2 + 8x - 4 < 0

Can't be factored with decomposition so yeahhhh, any suggestions?

2. Originally Posted by cjh824
x^2 + 8x - 4 < 0
Can't be factored with decomposition so
With real roots it can always be factored.
$x^2 + 8x - 4 = \left[ {x - \left( {\frac{{ - 8 + \sqrt {80} }}
{2}} \right)} \right]\left[ {x - \left( {\frac{{ - 8 - \sqrt {80} }}
{2}} \right)} \right]$

3. $x^{2}+8x-4<0\implies (x+4)^{2}<20\implies -2\sqrt{5}-4