Answer:
z ≤ 8
Explanation:
-9z ≥ -72
Isolate the variable, z. Treat the ≥ as a equal sign, what you do to one side, you do to the other. Divide -9 from both sides. Note that when you divide a negative number, you will flip the sign:
(-9z)/-9 ≥ (-72)/-9
z ≤ (-72)/(-9)
z ≤ 8
z ≤ 8 is your answer.
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