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

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

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Numerical solution:

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The solution

You have entered [src] 
(-x - 4)*(3*x + 3) = 0
(−x−4)(3x+3)=0\left(- x - 4\right) \left(3 x + 3\right) = 0
Simplify
Detail solution
Expand the expression in the equation
(−x−4)(3x+3)=0\left(- x - 4\right) \left(3 x + 3\right) = 0
We get the quadratic equation
−3x2−15x−12=0- 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:
x1=D−b2ax_{1} = \frac{\sqrt{D} - b}{2 a}
x2=−D−b2ax_{2} = \frac{- \sqrt{D} - b}{2 a}
where D = b^2 - 4*a*c - it is the discriminant.
Because
a=−3a = -3
b=−15b = -15
c=−12c = -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
x1=−4x_{1} = -4
x2=−1x_{2} = -1
The graph
05-20-15-10-510-500500
Plot the graph f1(x)
Plot the graph f2(x)
Sum and product of roots [src] 
sum
-4 - 1
−4−1-4 - 1 
=
-5
−5-5 
product
-4*(-1)
−−4- -4 
=
4
44 
4
Rapid solution [src] 
x1 = -4
x1=−4x_{1} = -4 
x2 = -1
x2=−1x_{2} = -1 
x2 = -1
Numerical answer [src] 
x1 = -1.0
x2 = -4.0
x2 = -4.0
The graph
(-x-4)*(3*x+3)=0 equation
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