80x-0.02x^2=0

Solution for 80x-0.02x^2=0 equation:

80x-0.02x^2=0

a = -0.02; b = 80; c = 0;
Δ = b2-4ac
Δ = 802-4·(-0.02)·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*-0.02}=\frac{-160}{-0.04}
=+4000
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(80)+80}{2*-0.02}=\frac{0}{-0.04}
=0
$