2x^2-390=0

Solution for 2x^2-390=0 equation:

2x^2-390=0

a = 2; b = 0; c = -390;
Δ = b2-4ac
Δ = 02-4·2·(-390)
Δ = 3120
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:

$\sqrt{\Delta}=\sqrt{3120}=\sqrt{16*195}=\sqrt{16}*\sqrt{195}=4\sqrt{195}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-4\sqrt{195}}{2*2}=\frac{0-4\sqrt{195}}{4}
=-\frac{4\sqrt{195}}{4}
=-\sqrt{195}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+4\sqrt{195}}{2*2}=\frac{0+4\sqrt{195}}{4}
=\frac{4\sqrt{195}}{4}
=\sqrt{195}
$