3x^2-18x=216

Solution for 3x^2-18x=216 equation:

3x^2-18x=216

We move all terms to the left:

3x^2-18x-(216)=0

a = 3; b = -18; c = -216;
Δ = b2-4ac
Δ = -182-4·3·(-216)
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{-(-18)-54}{2*3}=\frac{-36}{6}
=-6
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-18)+54}{2*3}=\frac{72}{6}
=12
$