Question 1136757
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            First,  it is not an equation,  since it has no right side and the equality sign.


            So,  we can talk about a polynomial,  but not about equation.


&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;And the question, &nbsp;if to formulate it correctly, &nbsp;should be &nbsp;<U>THIS</U> :


<pre>
                Find the roots of this polynomial.
</pre>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Second, the solution and the answer by @Boreal both are incorrect, since his factoring is incorrect.


&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Below find the correct solution.



<pre>
Introduce new variable  u = x^2.

Then your polynomial takes the form


    u^2 - 13u + 30


It can be factored in this way


    u^2 - 13u + 30 = (u-3)*(u-10) 


so, it has the roots  u = 3  and  u = 10, both positive.


It means, that the original polynomial has 4 (four) real roots  {{{sqrt(3)}}}, {{{-sqrt(3)}}},  {{{sqrt(10)}}}  and  {{{-sqrt(10)}}}.    <U>ANSWER</U>
</pre>

Solved.