x(x+0,1)+3,1=3,1

Solution for x(x+0,1)+3,1=3,1 equation:

x(x+0.1)+3.1=3.1

We move all terms to the left:

x(x+0.1)+3.1-(3.1)=0

We add all the numbers together, and all the variables

x(x+0.1)=0

We multiply parentheses

x^2+0.1x=0

a = 1; b = 0.1; c = 0;
Δ = b2-4ac
Δ = 0.12-4·1·0
Δ = 0.01
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{-(0.1)-\sqrt{0.01}}{2*1}=\frac{-0.1-\sqrt{0.01}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0.1)+\sqrt{0.01}}{2*1}=\frac{-0.1+\sqrt{0.01}}{2}
$