x(3x+3)=11

Solution for x(3x+3)=11 equation:

x(3x+3)=11

We move all terms to the left:

x(3x+3)-(11)=0

We multiply parentheses

3x^2+3x-11=0

a = 3; b = 3; c = -11;
Δ = b2-4ac
Δ = 32-4·3·(-11)
Δ = 141
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{-(3)-\sqrt{141}}{2*3}=\frac{-3-\sqrt{141}}{6}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(3)+\sqrt{141}}{2*3}=\frac{-3+\sqrt{141}}{6}
$