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    Okay I have this question, but I am getting the wrong answer, where am I going wrong?

    1 1/4 (4-2x) = 5/14 (6x+1)

    So first I make it look nicer

    5 (4-2x) / 4 = 5 (6x+1) / 14

    Then I cross multiply

    70(4-2x) = 20(6x+1)

    Then multiply out he brackets

    280-140x = 120x + 20

    And then rearrange

    140x-120x = 280+20 = 300, but that's not the answer, what have I done wrong?
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    (Original post by theoallen)
    Okay I have this question, but I am getting the wrong answer, where am I going wrong?

    1 1/4 (4-2x) = 5/14 (6x+1)

    So first I make it look nicer

    5 (4-2x) / 4 = 20 (not 5) (6x+1) / 14

    Then I cross multiply

    70(4-2x) = 20(6x+1)

    Then multiply out he brackets

    280-140x = 120x + 20

    And then rearrange

    140x-120x = 280+20 = 300, but that's not the answer, what have I done wrong?
    You didn't multiply the right hand side by 5
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    (Original post by theoallen)
    Okay I have this question, but I am getting the wrong answer, where am I going wrong?

    1 1/4 (4-2x) = 5/14 (6x+1)

    So first I make it look nicer

    5 (4-2x) / 4 = 5 (6x+1) / 14

    Then I cross multiply

    70(4-2x) = 20(6x+1)

    Then multiply out he brackets

    280-140x = 120x + 20

    And then rearrange

    140x-120x = 280+20 = 300, but that's not the answer, what have I done wrong?
    Is x=1 the answer by any chance?

    You seem to have done your final rearranging wrong.
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    (Original post by theoallen)

    280-140x = 120x + 20

    And then rearrange

    140x-120x = 280+20 = 300, but that's not the answer, what have I done wrong?
    That's almost right. You should use more steps:

    280 - 140x = 120x + 20

    Move the 140x over (it becomes a +)

    280 = 140x + 120x + 20

    Move the 20 over (it becomes a -)

    280 - 20 = 140x + 120x

    Simplify and solve.
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    (Original post by Axel Johann)
    You didn't multiply the right hand side by 5
    He didn't multiply the left hand side by 5 either then... he just converted from 1\frac{1}{4} \mathrm{ to } \frac{5}{4}
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    (Original post by Axel Johann)
    You didn't multiply the right hand side by 5
    Check again. You seem to have misunderstood.

    (Original post by natninja)
    Is x=1 the answer by any chance?
    Yep.
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    (Original post by natninja)
    He didn't multiply the left hand side by 5 either then... he just converted from 1\frac{1}{4} \mathrm{ to } \frac{5}{4}
    (Original post by Zacken)
    Check again. You seem to have misunderstood.



    Yep.
    Ohh i didnt see taht 1 haha :lol:

    whoops
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    (Original post by Axel Johann)
    You didn't multiply the right hand side by 5
    Am I meant too? Why would I multiply it by 5?
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    (Original post by theoallen)
    Am I meant too? Why would I multiply it by 5?
    Nah don't worry, i was wrong.
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    (Original post by theoallen)
    Am I meant too? Why would I multiply it by 5?
    Look at the other posts on the thread.
 
 
 
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