180=(2x)(x+9)

Solution for 180=(2x)(x+9) equation:

180=(2x)(x+9)

We move all terms to the left:

180-((2x)(x+9))=0


We calculate terms in parentheses: -(2x(x+9)), so:

2x(x+9)

We multiply parentheses

2x^2+18x

Back to the equation:

-(2x^2+18x)


We get rid of parentheses

-2x^2-18x+180=0

a = -2; b = -18; c = +180;
Δ = b2-4ac
Δ = -182-4·(-2)·180
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{-(-18)-42}{2*-2}=\frac{-24}{-4}
=+6
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-18)+42}{2*-2}=\frac{60}{-4}
=-15
$