4x2+60x-99=9

Solution for 4x2+60x-99=9 equation:

4x^2+60x-99=9

We move all terms to the left:

4x^2+60x-99-(9)=0

We add all the numbers together, and all the variables

4x^2+60x-108=0

a = 4; b = 60; c = -108;
Δ = b2-4ac
Δ = 602-4·4·(-108)
Δ = 5328
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{5328}=\sqrt{144*37}=\sqrt{144}*\sqrt{37}=12\sqrt{37}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(60)-12\sqrt{37}}{2*4}=\frac{-60-12\sqrt{37}}{8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(60)+12\sqrt{37}}{2*4}=\frac{-60+12\sqrt{37}}{8}
$