3x*x=396

Solution for 3x*x=396 equation:

3x*x=396

We move all terms to the left:

3x*x-(396)=0

Wy multiply elements

3x^2-396=0

a = 3; b = 0; c = -396;
Δ = b2-4ac
Δ = 02-4·3·(-396)
Δ = 4752
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{4752}=\sqrt{144*33}=\sqrt{144}*\sqrt{33}=12\sqrt{33}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-12\sqrt{33}}{2*3}=\frac{0-12\sqrt{33}}{6}
=-\frac{12\sqrt{33}}{6}
=-2\sqrt{33}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+12\sqrt{33}}{2*3}=\frac{0+12\sqrt{33}}{6}
=\frac{12\sqrt{33}}{6}
=2\sqrt{33}
$