Sum of real roots of the equation $x^2 + 5|x| +6 = 0$
2026-04-21 22:44:58.1776811498
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Sum of real roots of the equation $x^2 + 5|x| + 6 = 0$?
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Hint
$|x|=x\forall x\ge0$
$|x|=-x\forall x<0$
Case 1 $x\ge 0$
$x^2+5x+6=(x+2)(x+3)=0\Rightarrow x=-2,-3$ but we already assumed $x\ge 0$ so $(\Leftrightarrow)$
Case 2 $x<0$ then the equation becomes according to the definition of $|x|$
$x^2-5x+6=(x-2)(x-3)=0\Rightarrow x=2,3$ again $(\Leftrightarrow)$
$(\Leftrightarrow)$ is the sign of contradiction
Hint: It $r$ is a solution then so is $-r$
Note: After seeing Ryan's answer, I realized that the solution set is empty. Thus, Ryan's answer is the correct answer.
Now if we are looking for solutions inside $\mathbb{C}$, my hint can be used to deduce that either the solution set is infinite (hence the sum is undefined) or the sum is zero