[tex]-\dfrac{3}{8}c \geq 9[/tex]
First we need to multiply all the inequality by 8 to get rid of the denominator
[tex]-\dfrac{3}{8}c \geq 9|\times 8\\-3c\geq 72[/tex]
Now we need to divide all inequality by -3
[tex]-3c\geq 72|\div(-3)[/tex]
When dividing or multiplying an inequality by a negative number the inequality sign changes, so
[tex]c\leq -24[/tex]
Answer: c ≤ -24