4x2+12x-720=0

Solution for 4x2+12x-720=0 equation:

4x^2+12x-720=0

a = 4; b = 12; c = -720;
Δ = b2-4ac
Δ = 122-4·4·(-720)
Δ = 11664
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{11664}=108$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(12)-108}{2*4}=\frac{-120}{8}
=-15
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(12)+108}{2*4}=\frac{96}{8}
=12
$