3b(2b-1)+2b(b+3)=0

Solution for 3b(2b-1)+2b(b+3)=0 equation:

3b(2b-1)+2b(b+3)=0

We multiply parentheses

6b^2+2b^2-3b+6b=0

We add all the numbers together, and all the variables

8b^2+3b=0

a = 8; b = 3; c = 0;
Δ = b2-4ac
Δ = 32-4·8·0
Δ = 9
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{9}=3$
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(3)-3}{2*8}=\frac{-6}{16}
=-3/8
$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(3)+3}{2*8}=\frac{0}{16}
=0
$