What is the greatest common factor of 12a and 9a2

For these types of problems, You must look at the coefficients and variables separately and find the GCF for each. Then, combine the two
First, take 12 and 9
Factors of both
9- 1, 3, 9
12- 1, 2, 3, 4, 6, 12
So the gcf of 12 and 9 is 3
Now do the variables a and a^2
a^2 is just a twice
The GCF is a
Now combine a and 3
GCF is 3a

Answer: r=4.5  feetexplanation: radius  r  is half of the diameter  d,⇒r=d2=92=4.5  feetidk i could be wrong

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