0=2x^2-16x-18

Solution for 0=2x^2-16x-18 equation:

0=2x^2-16x-18

We move all terms to the left:

0-(2x^2-16x-18)=0

We add all the numbers together, and all the variables

-(2x^2-16x-18)=0

We get rid of parentheses

-2x^2+16x+18=0

a = -2; b = 16; c = +18;
Δ = b2-4ac
Δ = 162-4·(-2)·18
Δ = 400
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{400}=20$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(16)-20}{2*-2}=\frac{-36}{-4}
=+9
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(16)+20}{2*-2}=\frac{4}{-4}
=-1
$