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2^2-x-1=x^2-5*x-(-1-x^2)

2^2-x-1=x^2-5*x-(-1-x^2) equation

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Numerical solution:

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The solution

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             2              2
4 - x - 1 = x  - 5*x + 1 + x 
$$\left(4 - x\right) - 1 = \left(x^{2} + 1\right) + \left(x^{2} - 5 x\right)$$
Detail solution
Move right part of the equation to
left part with negative sign.

The equation is transformed from
$$\left(4 - x\right) - 1 = \left(x^{2} + 1\right) + \left(x^{2} - 5 x\right)$$
to
$$\left(\left(4 - x\right) - 1\right) + \left(\left(- x^{2} - 1\right) + \left(- x^{2} + 5 x\right)\right) = 0$$
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
$$a = -2$$
$$b = 4$$
$$c = 2$$
, then
D = b^2 - 4 * a * c = 

(4)^2 - 4 * (-2) * (2) = 32

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

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

or
$$x_{1} = 1 - \sqrt{2}$$
$$x_{2} = 1 + \sqrt{2}$$
Vieta's Theorem
rewrite the equation
$$\left(4 - x\right) - 1 = \left(x^{2} + 1\right) + \left(x^{2} - 5 x\right)$$
of
$$a x^{2} + b x + c = 0$$
as reduced quadratic equation
$$x^{2} + \frac{b x}{a} + \frac{c}{a} = 0$$
$$x^{2} - 2 x - 1 = 0$$
$$p x + q + x^{2} = 0$$
where
$$p = \frac{b}{a}$$
$$p = -2$$
$$q = \frac{c}{a}$$
$$q = -1$$
Vieta Formulas
$$x_{1} + x_{2} = - p$$
$$x_{1} x_{2} = q$$
$$x_{1} + x_{2} = 2$$
$$x_{1} x_{2} = -1$$
The graph
Rapid solution [src]
           ___
x1 = 1 - \/ 2 
$$x_{1} = 1 - \sqrt{2}$$
           ___
x2 = 1 + \/ 2 
$$x_{2} = 1 + \sqrt{2}$$
x2 = 1 + sqrt(2)
Sum and product of roots [src]
sum
      ___         ___
1 - \/ 2  + 1 + \/ 2 
$$\left(1 - \sqrt{2}\right) + \left(1 + \sqrt{2}\right)$$
=
2
$$2$$
product
/      ___\ /      ___\
\1 - \/ 2 /*\1 + \/ 2 /
$$\left(1 - \sqrt{2}\right) \left(1 + \sqrt{2}\right)$$
=
-1
$$-1$$
-1
Numerical answer [src]
x1 = -0.414213562373095
x2 = 2.41421356237309
x2 = 2.41421356237309
The graph
2^2-x-1=x^2-5*x-(-1-x^2) equation