1. Which of the following is the greatest common factorof the terms 48s5t3u2 and 40s3tu4?
A. 6s2t2u B. 8s2t2u C.6s3tu D. 8s3tu2
48s5t3u2 and 40s3tu4
Find the GCF for each variable one by one:
48:8*6
40:8*5
So GCF of 48s and 40s is 8s
That automatically only leaves us: B. 8s2t2u D. 8s3tu2
However from your question I could not understand whether you meant
OR 
Accordingly the GCF would change,but the basic concept to be followed is that you need to find the GCF of the variables and then combine it.
So we've found the GCF for '48s' and '40s',the same way find the GCF for the terms containing 't' and then for terms containing 'u',and combine it together to give you the answer you need.
2. What is the greatest common factor of the terms 14c2d and 42c3d?
A. 2c2d B. 3c C.14c2d D.7c2d
Again,theres a problem due to lack of formatting.
OR
OR
either way,following the same logic you can find the GCF for this one as well.
If you need any help,check your question and post again.
Hope this helps,
-Prabhat
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