Answer
$\le$
Work Step by Step
RECALL:
The Multiplication Property of Inequality states that for real number $a$, $b$, and $c\gt0$,
If $a \le b$, then $ac \le bc$
Thus. if $x \le 3$, then, multiplying $2$ to each side of the inequality gives:
$2(x) \le 2(3)
\\2x \le 6$
Therefore, the missing inequality symbol is $\le$.