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√(x-13)-√10-x=2 equation

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Numerical solution:

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The solution

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  ________     ____        
\/ x - 13  - \/ 10  - x = 2
$$- x + \left(\sqrt{x - 13} - \sqrt{10}\right) = 2$$
Detail solution
Given the equation
$$- x + \left(\sqrt{x - 13} - \sqrt{10}\right) = 2$$
$$\sqrt{x - 13} = x + 2 + \sqrt{10}$$
We raise the equation sides to 2-th degree
$$x - 13 = \left(x + 2 + \sqrt{10}\right)^{2}$$
$$x - 13 = x^{2} + 4 x + 2 \sqrt{10} x + 4 \sqrt{10} + 14$$
Transfer the right side of the equation left part with negative sign
$$- x^{2} - 2 \sqrt{10} x - 3 x - 27 - 4 \sqrt{10} = 0$$
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
$$a = -1$$
$$b = - 2 \sqrt{10} - 3$$
$$c = -27 - 4 \sqrt{10}$$
, then
D = b^2 - 4 * a * c = 

(-3 - 2*sqrt(10))^2 - 4 * (-1) * (-27 - 4*sqrt(10)) = -108 + (-3 - 2*sqrt(10))^2 - 16*sqrt(10)

Because D<0, then the equation
has no real roots,
but complex roots is exists.
x1 = (-b + sqrt(D)) / (2*a)

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

or
$$x_{1} = - \sqrt{10} - \frac{3}{2} - \frac{\sqrt{-108 - 16 \sqrt{10} + \left(- 2 \sqrt{10} - 3\right)^{2}}}{2}$$
$$x_{2} = - \sqrt{10} - \frac{3}{2} + \frac{\sqrt{-108 - 16 \sqrt{10} + \left(- 2 \sqrt{10} - 3\right)^{2}}}{2}$$
The graph
Sum and product of roots [src]
sum
                    _______________                       _______________
                   /          ____                       /          ____ 
  3     ____   I*\/  59 + 4*\/ 10       3     ____   I*\/  59 + 4*\/ 10  
- - - \/ 10  - -------------------- + - - - \/ 10  + --------------------
  2                     2               2                     2          
$$\left(- \sqrt{10} - \frac{3}{2} - \frac{i \sqrt{4 \sqrt{10} + 59}}{2}\right) + \left(- \sqrt{10} - \frac{3}{2} + \frac{i \sqrt{4 \sqrt{10} + 59}}{2}\right)$$
=
         ____
-3 - 2*\/ 10 
$$- 2 \sqrt{10} - 3$$
product
/                    _______________\ /                    _______________\
|                   /          ____ | |                   /          ____ |
|  3     ____   I*\/  59 + 4*\/ 10  | |  3     ____   I*\/  59 + 4*\/ 10  |
|- - - \/ 10  - --------------------|*|- - - \/ 10  + --------------------|
\  2                     2          / \  2                     2          /
$$\left(- \sqrt{10} - \frac{3}{2} - \frac{i \sqrt{4 \sqrt{10} + 59}}{2}\right) \left(- \sqrt{10} - \frac{3}{2} + \frac{i \sqrt{4 \sqrt{10} + 59}}{2}\right)$$
=
         ____
27 + 4*\/ 10 
$$4 \sqrt{10} + 27$$
27 + 4*sqrt(10)
Rapid solution [src]
                         _______________
                        /          ____ 
       3     ____   I*\/  59 + 4*\/ 10  
x1 = - - - \/ 10  - --------------------
       2                     2          
$$x_{1} = - \sqrt{10} - \frac{3}{2} - \frac{i \sqrt{4 \sqrt{10} + 59}}{2}$$
                         _______________
                        /          ____ 
       3     ____   I*\/  59 + 4*\/ 10  
x2 = - - - \/ 10  + --------------------
       2                     2          
$$x_{2} = - \sqrt{10} - \frac{3}{2} + \frac{i \sqrt{4 \sqrt{10} + 59}}{2}$$
x2 = -sqrt(10) - 3/2 + i*sqrt(4*sqrt(10) + 59)/2
Numerical answer [src]
x1 = -4.66227766016838 - 4.23228988375895*i
x2 = -4.66227766016838 + 4.23228988375895*i
x2 = -4.66227766016838 + 4.23228988375895*i