4x(x+2)+3(x+2)=0

Solution for 4x(x+2)+3(x+2)=0 equation:

4x(x+2)+3(x+2)=0

We multiply parentheses

4x^2+8x+3x+6=0

We add all the numbers together, and all the variables

4x^2+11x+6=0

a = 4; b = 11; c = +6;
Δ = b2-4ac
Δ = 112-4·4·6
Δ = 25
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{25}=5$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(11)-5}{2*4}=\frac{-16}{8}
=-2
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(11)+5}{2*4}=\frac{-6}{8}
=-3/4
$