1040=2x^2+12x

Solution for 1040=2x^2+12x equation:

1040=2x^2+12x

We move all terms to the left:

1040-(2x^2+12x)=0

We get rid of parentheses

-2x^2-12x+1040=0

a = -2; b = -12; c = +1040;
Δ = b2-4ac
Δ = -122-4·(-2)·1040
Δ = 8464
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{8464}=92$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-12)-92}{2*-2}=\frac{-80}{-4}
=+20
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-12)+92}{2*-2}=\frac{104}{-4}
=-26
$