0=2x^2+8x+7

Solution for 0=2x^2+8x+7 equation:

0=2x^2+8x+7

We move all terms to the left:

0-(2x^2+8x+7)=0

We add all the numbers together, and all the variables

-(2x^2+8x+7)=0

We get rid of parentheses

-2x^2-8x-7=0

a = -2; b = -8; c = -7;
Δ = b2-4ac
Δ = -82-4·(-2)·(-7)
Δ = 8
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:

$\sqrt{\Delta}=\sqrt{8}=\sqrt{4*2}=\sqrt{4}*\sqrt{2}=2\sqrt{2}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-8)-2\sqrt{2}}{2*-2}=\frac{8-2\sqrt{2}}{-4}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-8)+2\sqrt{2}}{2*-2}=\frac{8+2\sqrt{2}}{-4}
$