x=(30-2x)(18-2x)

Solution for x=(30-2x)(18-2x) equation:

x=(30-2x)(18-2x)

We move all terms to the left:

x-((30-2x)(18-2x))=0

We add all the numbers together, and all the variables

x-((-2x+30)(-2x+18))=0

We multiply parentheses ..

-((+4x^2-36x-60x+540))+x=0


We calculate terms in parentheses: -((+4x^2-36x-60x+540)), so:

(+4x^2-36x-60x+540)

We get rid of parentheses

4x^2-36x-60x+540

We add all the numbers together, and all the variables

4x^2-96x+540

Back to the equation:

-(4x^2-96x+540)


We add all the numbers together, and all the variables

x-(4x^2-96x+540)=0

We get rid of parentheses

-4x^2+x+96x-540=0

We add all the numbers together, and all the variables

-4x^2+97x-540=0

a = -4; b = 97; c = -540;
Δ = b2-4ac
Δ = 972-4·(-4)·(-540)
Δ = 769
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(97)-\sqrt{769}}{2*-4}=\frac{-97-\sqrt{769}}{-8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(97)+\sqrt{769}}{2*-4}=\frac{-97+\sqrt{769}}{-8}
$