Math

How to solve the two formulas for x+y=21 3x+4y=21

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asked by Tyler
  1. you can use a substraction-or-addition method or substitude method.
    So...
    x+y=21 you multiply both side by 3 3x+3y=63
    3x+4y=21
    ---------
    then you eliminate one variable
    you use the subtraction method
    -y=42
    y=-42
    then you solve for x by substituting the y
    x+(-42)=21
    x=63

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    posted by Vanessa
  2. i need to know how to turn 48.25 into a fration in simpilist forn

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    posted by brandon
  3. 48.25 =4825/100 = 193/4 = 48 1/4

    or just realize that .25 = 1/4
    so 48.25 = 48 1/4

    Please don't post a question as part of a previous thread, start a new topic
    That way you will have a much better chance at a tutor looking at it.

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    posted by Reiny
  4. 48.25 =4825/100 = 193/4 = 48 1/4

    or just realize that .25 = 1/4
    so 48.25 = 48 1/4

    Please don't post a question as part of a previous thread, start a new topic
    That way you will have a much better chance at a tutor looking at it.

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    2. 👎 0
    posted by Reiny

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