4x(x+1)=11

Solution for 4x(x+1)=11 equation:

4x(x+1)=11

We move all terms to the left:

4x(x+1)-(11)=0

We multiply parentheses

4x^2+4x-11=0

a = 4; b = 4; c = -11;
Δ = b2-4ac
Δ = 42-4·4·(-11)
Δ = 192
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:

$\sqrt{\Delta}=\sqrt{192}=\sqrt{64*3}=\sqrt{64}*\sqrt{3}=8\sqrt{3}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(4)-8\sqrt{3}}{2*4}=\frac{-4-8\sqrt{3}}{8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(4)+8\sqrt{3}}{2*4}=\frac{-4+8\sqrt{3}}{8}
$