(3x+3)(-1-3x)=0

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

(3x+3)(-1-3x)=0

We add all the numbers together, and all the variables

(3x+3)(-3x-1)=0

We multiply parentheses ..

(-9x^2-3x-9x-3)=0

We get rid of parentheses

-9x^2-3x-9x-3=0

We add all the numbers together, and all the variables

-9x^2-12x-3=0

a = -9; b = -12; c = -3;
Δ = b2-4ac
Δ = -122-4·(-9)·(-3)
Δ = 36
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{36}=6$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-12)-6}{2*-9}=\frac{6}{-18}
=-1/3
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-12)+6}{2*-9}=\frac{18}{-18}
=-1
$