120=(2x+2)(3x)

Solution for 120=(2x+2)(3x) equation:

120=(2x+2)(3x)

We move all terms to the left:

120-((2x+2)(3x))=0


We calculate terms in parentheses: -((2x+2)3x), so:

(2x+2)3x

We multiply parentheses

6x^2+6x

Back to the equation:

-(6x^2+6x)


We get rid of parentheses

-6x^2-6x+120=0

a = -6; b = -6; c = +120;
Δ = b2-4ac
Δ = -62-4·(-6)·120
Δ = 2916
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{2916}=54$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-6)-54}{2*-6}=\frac{-48}{-12}
=+4
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-6)+54}{2*-6}=\frac{60}{-12}
=-5
$