3x^2-x2=1200

Solution for 3x^2-x2=1200 equation:

3x^2-x2=1200

We move all terms to the left:

3x^2-x2-(1200)=0

We add all the numbers together, and all the variables

2x^2-1200=0

a = 2; b = 0; c = -1200;
Δ = b2-4ac
Δ = 02-4·2·(-1200)
Δ = 9600
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:

$\sqrt{\Delta}=\sqrt{9600}=\sqrt{1600*6}=\sqrt{1600}*\sqrt{6}=40\sqrt{6}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-40\sqrt{6}}{2*2}=\frac{0-40\sqrt{6}}{4}
=-\frac{40\sqrt{6}}{4}
=-10\sqrt{6}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+40\sqrt{6}}{2*2}=\frac{0+40\sqrt{6}}{4}
=\frac{40\sqrt{6}}{4}
=10\sqrt{6}
$