3x(x-2)=144

Solution for 3x(x-2)=144 equation:

3x(x-2)=144

We move all terms to the left:

3x(x-2)-(144)=0

We multiply parentheses

3x^2-6x-144=0

a = 3; b = -6; c = -144;
Δ = b2-4ac
Δ = -62-4·3·(-144)
Δ = 1764
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1764}=42$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-6)-42}{2*3}=\frac{-36}{6}
=-6
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-6)+42}{2*3}=\frac{48}{6}
=8
$