0=X^2+18x+70

Solution for 0=X^2+18x+70 equation:

0=X^2+18X+70

We move all terms to the left:

0-(X^2+18X+70)=0

We add all the numbers together, and all the variables

-(X^2+18X+70)=0

We get rid of parentheses

-X^2-18X-70=0

We add all the numbers together, and all the variables

-1X^2-18X-70=0

a = -1; b = -18; c = -70;
Δ = b2-4ac
Δ = -182-4·(-1)·(-70)
Δ = 44
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:

$\sqrt{\Delta}=\sqrt{44}=\sqrt{4*11}=\sqrt{4}*\sqrt{11}=2\sqrt{11}$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-18)-2\sqrt{11}}{2*-1}=\frac{18-2\sqrt{11}}{-2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-18)+2\sqrt{11}}{2*-1}=\frac{18+2\sqrt{11}}{-2}
$