(2m-8)(2m-5)=0

Solution for (2m-8)(2m-5)=0 equation:

(2m-8)(2m-5)=0

We multiply parentheses ..

(+4m^2-10m-16m+40)=0

We get rid of parentheses

4m^2-10m-16m+40=0

We add all the numbers together, and all the variables

4m^2-26m+40=0

a = 4; b = -26; c = +40;
Δ = b2-4ac
Δ = -262-4·4·40
Δ = 36
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$m_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$m_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{36}=6$
$m_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-26)-6}{2*4}=\frac{20}{8}
=2+1/2
$
$m_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-26)+6}{2*4}=\frac{32}{8}
=4
$