-2x^2-12x+14=0

Solution for -2x^2-12x+14=0 equation:

-2x^2-12x+14=0

a = -2; b = -12; c = +14;
Δ = b2-4ac
Δ = -122-4·(-2)·14
Δ = 256
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{256}=16$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-12)-16}{2*-2}=\frac{-4}{-4}
=1
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-12)+16}{2*-2}=\frac{28}{-4}
=-7
$