3=12x^2+1.2x+2

Solution for 3=12x^2+1.2x+2 equation:

3=12x^2+1.2x+2

We move all terms to the left:

3-(12x^2+1.2x+2)=0

We get rid of parentheses

-12x^2-1.2x-2+3=0

We add all the numbers together, and all the variables

-12x^2-1.2x+1=0

a = -12; b = -1.2; c = +1;
Δ = b2-4ac
Δ = -1.22-4·(-12)·1
Δ = 49.44
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{-(-1.2)-\sqrt{49.44}}{2*-12}=\frac{1.2-\sqrt{49.44}}{-24}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-1.2)+\sqrt{49.44}}{2*-12}=\frac{1.2+\sqrt{49.44}}{-24}
$