H=0.006x^2+0.6x

Solution for H=0.006x^2+0.6x equation:

=0.006H^2+0.6H

We move all terms to the left:

-(0.006H^2+0.6H)=0

We get rid of parentheses

-0.006H^2-0.6H=0

a = -0.006; b = -0.6; c = 0;
Δ = b2-4ac
Δ = -0.62-4·(-0.006)·0
Δ = 0.36
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$H_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$H_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$H_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-0.6)-\sqrt{0.36}}{2*-0.006}=\frac{0.6-\sqrt{0.36}}{-0.012}
$
$H_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-0.6)+\sqrt{0.36}}{2*-0.006}=\frac{0.6+\sqrt{0.36}}{-0.012}
$