x^2+3x=0.036

Solution for x^2+3x=0.036 equation:

x^2+3x=0.036

We move all terms to the left:

x^2+3x-(0.036)=0

We add all the numbers together, and all the variables

x^2+3x-0.036=0

a = 1; b = 3; c = -0.036;
Δ = b2-4ac
Δ = 32-4·1·(-0.036)
Δ = 9.144
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{-(3)-\sqrt{9.144}}{2*1}=\frac{-3-\sqrt{9.144}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(3)+\sqrt{9.144}}{2*1}=\frac{-3+\sqrt{9.144}}{2}
$