Units are simplified first when measurements are multiplied because the units can sometime be very large or small and do not have to be exact when measurements are precise.
Step-by-step explanation:
Yes, it is because the circumference is always 
times the amount of the radius.
Answer: i need help on that too :)
Step-by-step explanation:
Start by combing like terms. You will get 3x+12=51. Now subtract 12 from both sides (3x=39). Divide both sides by 3 (x=13). The answer is 13.
Answer:
What am I supposed to answer?
Step-by-step explanation:
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