2X^2+8x-138=0

Solution for 2X^2+8x-138=0 equation:

2X^2+8X-138=0

a = 2; b = 8; c = -138;
Δ = b2-4ac
Δ = 82-4·2·(-138)
Δ = 1168
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:

$\sqrt{\Delta}=\sqrt{1168}=\sqrt{16*73}=\sqrt{16}*\sqrt{73}=4\sqrt{73}$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(8)-4\sqrt{73}}{2*2}=\frac{-8-4\sqrt{73}}{4}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(8)+4\sqrt{73}}{2*2}=\frac{-8+4\sqrt{73}}{4}
$