330=(2x+8)(x+8)

Solution for 330=(2x+8)(x+8) equation:

330=(2x+8)(x+8)

We move all terms to the left:

330-((2x+8)(x+8))=0

We multiply parentheses ..

-((+2x^2+16x+8x+64))+330=0


We calculate terms in parentheses: -((+2x^2+16x+8x+64)), so:

(+2x^2+16x+8x+64)

We get rid of parentheses

2x^2+16x+8x+64

We add all the numbers together, and all the variables

2x^2+24x+64

Back to the equation:

-(2x^2+24x+64)


We get rid of parentheses

-2x^2-24x-64+330=0

We add all the numbers together, and all the variables

-2x^2-24x+266=0

a = -2; b = -24; c = +266;
Δ = b2-4ac
Δ = -242-4·(-2)·266
Δ = 2704
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{2704}=52$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-24)-52}{2*-2}=\frac{-28}{-4}
=+7
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-24)+52}{2*-2}=\frac{76}{-4}
=-19
$