-24=3x^2-27x

Solution for -24=3x^2-27x equation:

-24=3x^2-27x

We move all terms to the left:

-24-(3x^2-27x)=0

We get rid of parentheses

-3x^2+27x-24=0

a = -3; b = 27; c = -24;
Δ = b2-4ac
Δ = 272-4·(-3)·(-24)
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{-(27)-21}{2*-3}=\frac{-48}{-6}
=+8
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(27)+21}{2*-3}=\frac{-6}{-6}
=1
$