(X+12)(x+18)=432

Solution for (X+12)(x+18)=432 equation:

(X+12)(X+18)=432

We move all terms to the left:

(X+12)(X+18)-(432)=0

We multiply parentheses ..

(+X^2+18X+12X+216)-432=0

We get rid of parentheses

X^2+18X+12X+216-432=0

We add all the numbers together, and all the variables

X^2+30X-216=0

a = 1; b = 30; c = -216;
Δ = b2-4ac
Δ = 302-4·1·(-216)
Δ = 1764
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1764}=42$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(30)-42}{2*1}=\frac{-72}{2}
=-36
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(30)+42}{2*1}=\frac{12}{2}
=6
$