0.09x-0.003x^2=0.13

Solution for 0.09x-0.003x^2=0.13 equation:

0.09x-0.003x^2=0.13

We move all terms to the left:

0.09x-0.003x^2-(0.13)=0

We add all the numbers together, and all the variables

-0.003x^2+0.09x-0.13=0

a = -0.003; b = 0.09; c = -0.13;
Δ = b2-4ac
Δ = 0.092-4·(-0.003)·(-0.13)
Δ = 0.00654
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0.09)-\sqrt{0.00654}}{2*-0.003}=\frac{-0.09-\sqrt{0.00654}}{-0.006}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0.09)+\sqrt{0.00654}}{2*-0.003}=\frac{-0.09+\sqrt{0.00654}}{-0.006}
$