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ejanderson
Posts:
3
From:
Nebraska
Registered:
2/14/10


Better Answer over another?
Posted:
Feb 14, 2010 1:35 PM


Hello, I'm going through a "selfteaching" algebra book and am surprised at how much of it I remember. Throughout the book they have several quickcheck tests. I've been a little confused as to the answer they put in the book compared with mine. Here are two examples:
1:Combine Like Terms: 2k3ab+4y+7abab My answer was this: 2k+3ab+4y The book answer was: 3ab+2ky+4
2:Subtract Horizontally: 4n+2k3m from 8n5km My answer was this: 7k+2m+4n The book answer was: +4n7k+2m
My confusion comes from the contrast in the book answers. In problem #1, the book seems to use alphabetical order of the literal factors (ab, then k, then y). However, in problem #2, the answer has the literal factors out of order, whereas my answer for #2 did have them in alphabetical order. Are my answers correct? If they are correct, what makes the book answers "better"? If they are not correct, what am I forgetting about or not understanding when it comes to putting the terms into order for my answer? Any help or clarification would be greatly appreciated!
Sincerely, Evan



