Answer:
-3mn
Step-by-step explanation:
It seems you might be missing some of the question, as you haven't given what m and n are equal to.
If the question has just given you x, then you would simply just simplify it to get -3mn.
It would be equivalent to x=8
<h3>
Answer: Circumference is approximately 75.36 feet</h3>
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Work Shown:
d = diameter = 24 ft
pi = 3.14 approx
C = circumference of circle
C = pi*d
C = 3.14*24
C = 75.36 feet