2x^2-70x-820=0

Solution for 2x^2-70x-820=0 equation:

2x^2-70x-820=0

a = 2; b = -70; c = -820;
Δ = b2-4ac
Δ = -702-4·2·(-820)
Δ = 11460
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:

$\sqrt{\Delta}=\sqrt{11460}=\sqrt{4*2865}=\sqrt{4}*\sqrt{2865}=2\sqrt{2865}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-70)-2\sqrt{2865}}{2*2}=\frac{70-2\sqrt{2865}}{4}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-70)+2\sqrt{2865}}{2*2}=\frac{70+2\sqrt{2865}}{4}
$