2X^2+2x-155=0

Solution for 2X^2+2x-155=0 equation:

2X^2+2X-155=0

a = 2; b = 2; c = -155;
Δ = b2-4ac
Δ = 22-4·2·(-155)
Δ = 1244
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:

$\sqrt{\Delta}=\sqrt{1244}=\sqrt{4*311}=\sqrt{4}*\sqrt{311}=2\sqrt{311}$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(2)-2\sqrt{311}}{2*2}=\frac{-2-2\sqrt{311}}{4}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(2)+2\sqrt{311}}{2*2}=\frac{-2+2\sqrt{311}}{4}
$