(60+3x)*(80-2x)=0

Solution for (60+3x)*(80-2x)=0 equation:

(60+3x)(80-2x)=0

We add all the numbers together, and all the variables

(3x+60)(-2x+80)=0

We multiply parentheses ..

(-6x^2+240x-120x+4800)=0

We get rid of parentheses

-6x^2+240x-120x+4800=0

We add all the numbers together, and all the variables

-6x^2+120x+4800=0

a = -6; b = 120; c = +4800;
Δ = b2-4ac
Δ = 1202-4·(-6)·4800
Δ = 129600
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{129600}=360$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(120)-360}{2*-6}=\frac{-480}{-12}
=+40
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(120)+360}{2*-6}=\frac{240}{-12}
=-20
$