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2*x^2-8*x=0

2*x^2-8*x=0 equation

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Numerical solution:

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The solution

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   2          
2*x  - 8*x = 0
2x28x=02 x^{2} - 8 x = 0
Detail solution
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=Db2ax_{1} = \frac{\sqrt{D} - b}{2 a}
x2=Db2ax_{2} = \frac{- \sqrt{D} - b}{2 a}
where D = b^2 - 4*a*c - it is the discriminant.
Because
a=2a = 2
b=8b = -8
c=0c = 0
, then
D = b^2 - 4 * a * c = 

(-8)^2 - 4 * (2) * (0) = 64

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=0x_{2} = 0
Vieta's Theorem
rewrite the equation
2x28x=02 x^{2} - 8 x = 0
of
ax2+bx+c=0a x^{2} + b x + c = 0
as reduced quadratic equation
x2+bxa+ca=0x^{2} + \frac{b x}{a} + \frac{c}{a} = 0
x24x=0x^{2} - 4 x = 0
px+q+x2=0p x + q + x^{2} = 0
where
p=bap = \frac{b}{a}
p=4p = -4
q=caq = \frac{c}{a}
q=0q = 0
Vieta Formulas
x1+x2=px_{1} + x_{2} = - p
x1x2=qx_{1} x_{2} = q
x1+x2=4x_{1} + x_{2} = 4
x1x2=0x_{1} x_{2} = 0
The graph
05-15-10-5101520-500500
Rapid solution [src]
x1 = 0
x1=0x_{1} = 0
x2 = 4
x2=4x_{2} = 4
x2 = 4
Sum and product of roots [src]
sum
4
44
=
4
44
product
0*4
040 \cdot 4
=
0
00
0
Numerical answer [src]
x1 = 4.0
x2 = 0.0
x2 = 0.0
The graph
2*x^2-8*x=0 equation