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Homework Help: Expand and simplify brackets

  1. Feb 16, 2010 #1
    I'm studying expanding and simplifying brackets and I'm not sure how to tackle this type of problem:

    -3e + (e - 1)

    It's the + sign before the bracket that confuses me. My (wrong) answer was:
    -3e squared + 3e
    I guess that would have been right if that + wasn't there.
    The answer is:
    -3e - 1

    How do I get to that?
     
  2. jcsd
  3. Feb 16, 2010 #2
    No...that is not the answer...it should be -2e - 1.
    To tackle the problem, just apply the sign to the terms inside the brackets.
    So, -3e + (e-1) = -3e + e - 1
    (+ * + = +, + * - = -)
     
  4. Feb 16, 2010 #3
    Got it! Thanks once again Fightfish!
     
  5. Feb 16, 2010 #4

    Mark44

    Staff: Mentor

    In this expression the parentheses (brackets are [ ]) are completely unnecessary.
    -3e + (e - 1) = -3e + e -1 = -2e - 1.

    You are interpreting this problem incorrectly as a multiplication problem even though the operation is really addition. In other words, you are working this problem:
    -3e(e -1) = -3e2 + 3e.


     
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