-3x(x-2)-5x=-18

Solution for -3x(x-2)-5x=-18 equation:

-3x(x-2)-5x=-18

We move all terms to the left:

-3x(x-2)-5x-(-18)=0

We add all the numbers together, and all the variables

-5x-3x(x-2)+18=0

We multiply parentheses

-3x^2-5x+6x+18=0

We add all the numbers together, and all the variables

-3x^2+x+18=0

a = -3; b = 1; c = +18;
Δ = b2-4ac
Δ = 12-4·(-3)·18
Δ = 217
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{-(1)-\sqrt{217}}{2*-3}=\frac{-1-\sqrt{217}}{-6}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(1)+\sqrt{217}}{2*-3}=\frac{-1+\sqrt{217}}{-6}
$