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-2*x+5*sqrt(x)-2=0 equation

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Numerical solution:

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The solution

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-2*x + 5*\/ x  - 2 = 0
$$\left(5 \sqrt{x} - 2 x\right) - 2 = 0$$
Detail solution
Given the equation
$$\left(5 \sqrt{x} - 2 x\right) - 2 = 0$$
$$5 \sqrt{x} = 2 x + 2$$
We raise the equation sides to 2-th degree
$$25 x = \left(2 x + 2\right)^{2}$$
$$25 x = 4 x^{2} + 8 x + 4$$
Transfer the right side of the equation left part with negative sign
$$- 4 x^{2} + 17 x - 4 = 0$$
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
$$a = -4$$
$$b = 17$$
$$c = -4$$
, then
D = b^2 - 4 * a * c = 

(17)^2 - 4 * (-4) * (-4) = 225

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

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

or
$$x_{1} = \frac{1}{4}$$
$$x_{2} = 4$$

Because
$$\sqrt{x} = \frac{2 x}{5} + \frac{2}{5}$$
and
$$\sqrt{x} \geq 0$$
then
$$\frac{2 x}{5} + \frac{2}{5} \geq 0$$
or
$$-1 \leq x$$
$$x < \infty$$
The final answer:
$$x_{1} = \frac{1}{4}$$
$$x_{2} = 4$$
The graph
Rapid solution [src]
x1 = 1/4
$$x_{1} = \frac{1}{4}$$
x2 = 4
$$x_{2} = 4$$
x2 = 4
Sum and product of roots [src]
sum
4 + 1/4
$$\frac{1}{4} + 4$$
=
17/4
$$\frac{17}{4}$$
product
4
-
4
$$\frac{4}{4}$$
=
1
$$1$$
1
Numerical answer [src]
x1 = 4.0
x2 = 0.25
x2 = 0.25