4m(m-10)=0

Solution for 4m(m-10)=0 equation:

4m(m-10)=0

We multiply parentheses

4m^2-40m=0

a = 4; b = -40; c = 0;
Δ = b2-4ac
Δ = -402-4·4·0
Δ = 1600
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$m_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$m_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1600}=40$
$m_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-40)-40}{2*4}=\frac{0}{8}
=0
$
$m_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-40)+40}{2*4}=\frac{80}{8}
=10
$