SOLUTION: How do I write this square as a trinomial: (3u-1)^2

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Question 705557: How do I write this square as a trinomial: (3u-1)^2
Answer by jsmallt9(3758) About Me  (Show Source):
You can put this solution on YOUR website!
Method 1: One of the patterns you should have learned by now is:
%28a-b%29%5E2+=+a%5E2-2ab%2Bb%5E2
This pattern can be used to multiply %283u-1%29%5E2 with the "a" being "3u" and the "b" being "1":
%283u-1%29%5E2
%283u%29%5E2-2%2A%283u%29%281%29+%2B%281%29%5E2 (Note the parentheses. Always a good idea when using patterns!)
9u%5E2-6u+%2B1

Method 2:
%283u-1%29%5E2 means (3u-1)(3u-1). You can use FOIL to multiply this out. (After you multiply and then add like terms, you get the same answer as method 1 .)