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

(-x-4)(3x+3)=0 equation

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Numerical solution:

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The solution

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(-x - 4)*(3*x + 3) = 0
$$\left(- x - 4\right) \left(3 x + 3\right) = 0$$
Detail solution
Expand the expression in the equation
$$\left(- x - 4\right) \left(3 x + 3\right) = 0$$
We get the quadratic equation
$$- 3 x^{2} - 15 x - 12 = 0$$
This equation is of the form
a*x^2 + b*x + c = 0

A quadratic equation can be solved
using the discriminant.
The roots of the quadratic equation:
$$x_{1} = \frac{\sqrt{D} - b}{2 a}$$
$$x_{2} = \frac{- \sqrt{D} - b}{2 a}$$
where D = b^2 - 4*a*c - it is the discriminant.
Because
$$a = -3$$
$$b = -15$$
$$c = -12$$
, then
D = b^2 - 4 * a * c = 

(-15)^2 - 4 * (-3) * (-12) = 81

Because D > 0, then the equation has two roots.
x1 = (-b + sqrt(D)) / (2*a)

x2 = (-b - sqrt(D)) / (2*a)

or
$$x_{1} = -4$$
$$x_{2} = -1$$
The graph
Sum and product of roots [src]
sum
-4 - 1
$$-4 - 1$$
=
-5
$$-5$$
product
-4*(-1)
$$- -4$$
=
4
$$4$$
4
Rapid solution [src]
x1 = -4
$$x_{1} = -4$$
x2 = -1
$$x_{2} = -1$$
x2 = -1
Numerical answer [src]
x1 = -1.0
x2 = -4.0
x2 = -4.0
The graph
(-x-4)(3x+3)=0 equation