-3x(3x-8)=3x

Solution for -3x(3x-8)=3x equation:

-3x(3x-8)=3x

We move all terms to the left:

-3x(3x-8)-(3x)=0

We add all the numbers together, and all the variables

-3x-3x(3x-8)=0

We multiply parentheses

-9x^2-3x+24x=0

We add all the numbers together, and all the variables

-9x^2+21x=0

a = -9; b = 21; c = 0;
Δ = b2-4ac
Δ = 212-4·(-9)·0
Δ = 441
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{441}=21$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(21)-21}{2*-9}=\frac{-42}{-18}
=2+1/3
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(21)+21}{2*-9}=\frac{0}{-18}
=0
$