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2x^2-8=0

2x^2-8=0 equation

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Numerical solution:

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The solution

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2*x  - 8 = 0
$$2 x^{2} - 8 = 0$$
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:
$$x_{1} = \frac{\sqrt{D} - b}{2 a}$$
$$x_{2} = \frac{- \sqrt{D} - b}{2 a}$$
where D = b^2 - 4*a*c - it is the discriminant.
Because
$$a = 2$$
$$b = 0$$
$$c = -8$$
, then
D = b^2 - 4 * a * c = 

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

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

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

or
$$x_{1} = 2$$
$$x_{2} = -2$$
Vieta's Theorem
rewrite the equation
$$2 x^{2} - 8 = 0$$
of
$$a x^{2} + b x + c = 0$$
as reduced quadratic equation
$$x^{2} + \frac{b x}{a} + \frac{c}{a} = 0$$
$$x^{2} - 4 = 0$$
$$p x + q + x^{2} = 0$$
where
$$p = \frac{b}{a}$$
$$p = 0$$
$$q = \frac{c}{a}$$
$$q = -4$$
Vieta Formulas
$$x_{1} + x_{2} = - p$$
$$x_{1} x_{2} = q$$
$$x_{1} + x_{2} = 0$$
$$x_{1} x_{2} = -4$$
The graph
Rapid solution [src]
x1 = -2
$$x_{1} = -2$$
x2 = 2
$$x_{2} = 2$$
x2 = 2
Sum and product of roots [src]
sum
-2 + 2
$$-2 + 2$$
=
0
$$0$$
product
-2*2
$$- 4$$
=
-4
$$-4$$
-4
Numerical answer [src]
x1 = -2.0
x2 = 2.0
x2 = 2.0
The graph
2x^2-8=0 equation