0=7.2x^2-33.1x+18.3

Solution for 0=7.2x^2-33.1x+18.3 equation:

0=7.2x^2-33.1x+18.3

We move all terms to the left:

0-(7.2x^2-33.1x+18.3)=0

We add all the numbers together, and all the variables

-(7.2x^2-33.1x+18.3)=0

We get rid of parentheses

-7.2x^2+33.1x-18.3=0

a = -7.2; b = 33.1; c = -18.3;
Δ = b2-4ac
Δ = 33.12-4·(-7.2)·(-18.3)
Δ = 568.57
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(33.1)-\sqrt{568.57}}{2*-7.2}=\frac{-33.1-\sqrt{568.57}}{-14.4}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(33.1)+\sqrt{568.57}}{2*-7.2}=\frac{-33.1+\sqrt{568.57}}{-14.4}
$