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Homework Help: Easy Algebra problem(s)

  1. Dec 12, 2008 #1
    EDIT: Problem Solved, please delete.
    Last edited: Dec 12, 2008
  2. jcsd
  3. Dec 12, 2008 #2


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    How do you determine cost? Total cost is the sum of the individual item costs. You will have two linear equations and two unknown numbers. Your variables are the price of the shirt and the price of the tie.
  4. Dec 12, 2008 #3
    Make two equations. Let X be the cost of a shirt, and Y be the price of a tie, or use whatever variables you want. You have enough information to write two equations keeping your two prices as two variables.

    Below are the important sentences you turn into equations.

    6 shirts and 3 ties cost $79.50
    3 shirts and 2 ties cost $41
  5. Dec 12, 2008 #4
    Wouldn't that turn into a graph though? There's three answers to choose from.

    A.) $10.00
    B.) $11.00
    C.) $12.00

    So I did the math and I got 6x+3y=79.50 and 3x+2y =41. Then I got 3x+y=38.50, and I don't know how to go from there since there are two variables.
  6. Dec 12, 2008 #5
    Okay this is what I got. Each shirt costs 12 dollars and plugged it in and it seemed to work. 3shirts + 2 ties = 41, so 3x12 + 2x2.50 = 41, 36+5= 41.

    So is $12.00 right?
  7. Dec 13, 2008 #6
    6x + 3y=79.5
    3x + 2y=41

    Now, I mulitply the second equation by (-2), so that I got:


    Out of there:
    One tie costs ($):
    One shirt costs($):
    6x + 3*2.5=79.5
    6x = 72

  8. Dec 13, 2008 #7


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    The initial posting was altered; post #1 was changed and the original message is gone in that posting (except for a quote from the original).
    Last edited: Dec 13, 2008
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