Answer:
a ≤ 20/3
Explanation:
Subtract 4 from both sides, obtaining:
-3a ≥ -20. Dividing both sides by -3, we get a ≤ 20/3.
Note that because this is an inequality, and because we've divided all terms by a negative number, we must change the direction of the inequality symbol from ≥ to ≤.