0=x2+18x+45

Solution for 0=x2+18x+45 equation:

0=x2+18x+45

We move all terms to the left:

0-(x2+18x+45)=0

We add all the numbers together, and all the variables

-(+x^2+18x+45)+0=0

We add all the numbers together, and all the variables

-(+x^2+18x+45)=0

We get rid of parentheses

-x^2-18x-45=0

We add all the numbers together, and all the variables

-1x^2-18x-45=0

a = -1; b = -18; c = -45;
Δ = b2-4ac
Δ = -182-4·(-1)·(-45)
Δ = 144
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{144}=12$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-18)-12}{2*-1}=\frac{6}{-2}
=-3
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-18)+12}{2*-1}=\frac{30}{-2}
=-15
$