Answer
The solution set is $[-6, \infty)$
Work Step by Step
The idea is to isolate x on one side.
Adding, subtracting or multiplying/dividing with a positive number preserves order (the inequality symbol remains).
Multiplying/dividing with a negative number inverts the order (the inequality symbol changes).
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$-5x \leq 30\qquad $ ... $/\div(-5)$, (negative!)
$ x \geq -6$
The solution set is $[-6, \infty)$
