4x=0.016x^2

Solution for 4x=0.016x^2 equation:

4x=0.016x^2

We move all terms to the left:

4x-(0.016x^2)=0

We get rid of parentheses

-0.016x^2+4x=0

a = -0.016; b = 4; c = 0;
Δ = b2-4ac
Δ = 42-4·(-0.016)·0
Δ = 16
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{16}=4$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(4)-4}{2*-0.016}=\frac{-8}{-0.032}
=+250
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(4)+4}{2*-0.016}=\frac{0}{-0.032}
=0
$