12x^2+72x-84=0

Solution for 12x^2+72x-84=0 equation:

12x^2+72x-84=0

a = 12; b = 72; c = -84;
Δ = b2-4ac
Δ = 722-4·12·(-84)
Δ = 9216
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{9216}=96$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(72)-96}{2*12}=\frac{-168}{24}
=-7
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(72)+96}{2*12}=\frac{24}{24}
=1
$