225=3x^2

Solution for 225=3x^2 equation:

225=3x^2

We move all terms to the left:

225-(3x^2)=0

a = -3; b = 0; c = +225;
Δ = b2-4ac
Δ = 02-4·(-3)·225
Δ = 2700
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:

$\sqrt{\Delta}=\sqrt{2700}=\sqrt{900*3}=\sqrt{900}*\sqrt{3}=30\sqrt{3}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-30\sqrt{3}}{2*-3}=\frac{0-30\sqrt{3}}{-6}
=-\frac{30\sqrt{3}}{-6}
=-\frac{5\sqrt{3}}{-1}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+30\sqrt{3}}{2*-3}=\frac{0+30\sqrt{3}}{-6}
=\frac{30\sqrt{3}}{-6}
=\frac{5\sqrt{3}}{-1}
$