18x^2-12x=9x^2-18x

Solution for 18x^2-12x=9x^2-18x equation:

18x^2-12x=9x^2-18x

We move all terms to the left:

18x^2-12x-(9x^2-18x)=0

We get rid of parentheses

18x^2-9x^2-12x+18x=0

We add all the numbers together, and all the variables

9x^2+6x=0

a = 9; b = 6; c = 0;
Δ = b2-4ac
Δ = 62-4·9·0
Δ = 36
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{36}=6$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(6)-6}{2*9}=\frac{-12}{18}
=-2/3
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(6)+6}{2*9}=\frac{0}{18}
=0
$