(-m-3)(2m-4)=0

Solution for (-m-3)(2m-4)=0 equation:

(-m-3)(2m-4)=0

We add all the numbers together, and all the variables

(-1m-3)(2m-4)=0

We multiply parentheses ..

(-2m^2+4m-6m+12)=0

We get rid of parentheses

-2m^2+4m-6m+12=0

We add all the numbers together, and all the variables

-2m^2-2m+12=0

a = -2; b = -2; c = +12;
Δ = b2-4ac
Δ = -22-4·(-2)·12
Δ = 100
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$m_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$m_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{100}=10$
$m_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-2)-10}{2*-2}=\frac{-8}{-4}
=+2
$
$m_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-2)+10}{2*-2}=\frac{12}{-4}
=-3
$