4x(5-3x)=0

Solution for 4x(5-3x)=0 equation:

4x(5-3x)=0

We add all the numbers together, and all the variables

4x(-3x+5)=0

We multiply parentheses

-12x^2+20x=0

a = -12; b = 20; c = 0;
Δ = b2-4ac
Δ = 202-4·(-12)·0
Δ = 400
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{400}=20$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(20)-20}{2*-12}=\frac{-40}{-24}
=1+2/3
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(20)+20}{2*-12}=\frac{0}{-24}
=0
$