X=11-3x2

Solution for X=11-3x2 equation:

X=11-3X^2

We move all terms to the left:

X-(11-3X^2)=0

We get rid of parentheses

3X^2+X-11=0

a = 3; b = 1; c = -11;
Δ = b2-4ac
Δ = 12-4·3·(-11)
Δ = 133
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)-\sqrt{133}}{2*3}=\frac{-1-\sqrt{133}}{6}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(1)+\sqrt{133}}{2*3}=\frac{-1+\sqrt{133}}{6}
$