(x^2)/4-20x=0

Solution for (x^2)/4-20x=0 equation:

(x^2)/4-20x=0

We multiply all the terms by the denominator


x^2-20x*4=0

Wy multiply elements

x^2-80x=0

a = 1; b = -80; c = 0;
Δ = b2-4ac
Δ = -802-4·1·0
Δ = 6400
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{6400}=80$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-80)-80}{2*1}=\frac{0}{2}
=0
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-80)+80}{2*1}=\frac{160}{2}
=80
$