6x2-800-40x-2x2=0

Solution for 6x2-800-40x-2x2=0 equation:

6x^2-800-40x-2x^2=0

We add all the numbers together, and all the variables

4x^2-40x-800=0

a = 4; b = -40; c = -800;
Δ = b2-4ac
Δ = -402-4·4·(-800)
Δ = 14400
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{14400}=120$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-40)-120}{2*4}=\frac{-80}{8}
=-10
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-40)+120}{2*4}=\frac{160}{8}
=20
$