420=(2x-2)*x

Solution for 420=(2x-2)*x equation:

420=(2x-2)*x

We move all terms to the left:

420-((2x-2)*x)=0


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

(2x-2)*x

We multiply parentheses

2x^2-2x

Back to the equation:

-(2x^2-2x)


We get rid of parentheses

-2x^2+2x+420=0

a = -2; b = 2; c = +420;
Δ = b2-4ac
Δ = 22-4·(-2)·420
Δ = 3364
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{3364}=58$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(2)-58}{2*-2}=\frac{-60}{-4}
=+15
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(2)+58}{2*-2}=\frac{56}{-4}
=-14
$