2x2-30x-12=0

Solution for 2x2-30x-12=0 equation:

2x^2-30x-12=0

a = 2; b = -30; c = -12;
Δ = b2-4ac
Δ = -302-4·2·(-12)
Δ = 996
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:

$\sqrt{\Delta}=\sqrt{996}=\sqrt{4*249}=\sqrt{4}*\sqrt{249}=2\sqrt{249}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-30)-2\sqrt{249}}{2*2}=\frac{30-2\sqrt{249}}{4}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-30)+2\sqrt{249}}{2*2}=\frac{30+2\sqrt{249}}{4}
$