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sqrt(3x^2+4x-6)=2 equation

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Numerical solution:

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The solution

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  /    2               
\/  3*x  + 4*x - 6  = 2
$$\sqrt{\left(3 x^{2} + 4 x\right) - 6} = 2$$
Detail solution
Given the equation
$$\sqrt{\left(3 x^{2} + 4 x\right) - 6} = 2$$
$$\sqrt{3 x^{2} + 4 x - 6} = 2$$
We raise the equation sides to 2-th degree
$$3 x^{2} + 4 x - 6 = 4$$
$$3 x^{2} + 4 x - 6 = 4$$
Transfer the right side of the equation left part with negative sign
$$3 x^{2} + 4 x - 10 = 0$$
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
$$a = 3$$
$$b = 4$$
$$c = -10$$
, then
D = b^2 - 4 * a * c = 

(4)^2 - 4 * (3) * (-10) = 136

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

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

or
$$x_{1} = - \frac{2}{3} + \frac{\sqrt{34}}{3}$$
$$x_{2} = - \frac{\sqrt{34}}{3} - \frac{2}{3}$$

Because
$$\sqrt{3 x^{2} + 4 x - 6} = 2$$
and
$$\sqrt{3 x^{2} + 4 x - 6} \geq 0$$
then
$$2 \geq 0$$
The final answer:
$$x_{1} = - \frac{2}{3} + \frac{\sqrt{34}}{3}$$
$$x_{2} = - \frac{\sqrt{34}}{3} - \frac{2}{3}$$
The graph
Rapid solution [src]
             ____
       2   \/ 34 
x1 = - - + ------
       3     3   
$$x_{1} = - \frac{2}{3} + \frac{\sqrt{34}}{3}$$
             ____
       2   \/ 34 
x2 = - - - ------
       3     3   
$$x_{2} = - \frac{\sqrt{34}}{3} - \frac{2}{3}$$
x2 = -sqrt(34)/3 - 2/3
Sum and product of roots [src]
sum
        ____           ____
  2   \/ 34      2   \/ 34 
- - + ------ + - - - ------
  3     3        3     3   
$$\left(- \frac{\sqrt{34}}{3} - \frac{2}{3}\right) + \left(- \frac{2}{3} + \frac{\sqrt{34}}{3}\right)$$
=
-4/3
$$- \frac{4}{3}$$
product
/        ____\ /        ____\
|  2   \/ 34 | |  2   \/ 34 |
|- - + ------|*|- - - ------|
\  3     3   / \  3     3   /
$$\left(- \frac{2}{3} + \frac{\sqrt{34}}{3}\right) \left(- \frac{\sqrt{34}}{3} - \frac{2}{3}\right)$$
=
-10/3
$$- \frac{10}{3}$$
-10/3
Numerical answer [src]
x1 = -2.61031729828177
x2 = 1.27698396494843
x2 = 1.27698396494843