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    Hi All,

    I am new to this forum so I apoligise if I'm doing this wrong.

    I have just started to take my A level in Maths, I am studying from home through one of those companys you find on the internet.

    Only the problem is that when I have been working through C1, I some how can't get my answers for Simultaneous equations right, I have checked the back of the book and I'm all wrong. I have sat here for about four hours over the last few days, and I'm just getting really frustrated, if I can't do this, how can I do everything else

    Can some one help me please, I have studied all the methods in my GCSE and C1 book, but even if I follow the instructions perfectly, I'm not getting what I should be

    Its such a simple equation but can someone help? I would be forever grateful if you could just point out where I go wrong.

    5x+2y=11
    4x+3y=13

    So the book says that I should make the coefficients of Y the same so that gives me:

    15x+6y=33
    8x+6y=26

    So then add the X's = 23x and add the totals = 59

    Which I can tell right off is wrong. Please I don't need the answers just need to know where I'm going horribly wrong. x
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    You need to take the X's and totals, not add them, 'cause you're taking the equations away from one another to cancel out the Y's
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    You need to subtract, not add, to get rid of the 6y.

    Edit // Too slow.
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    i.e

    (

15x+6y=33) -
    (

8x+6y=26

)
    = 7x=7
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    Ahhh right, that makes much more sense lol

    I used to be sooo good at all this stuff but it all seems to be hibernating upstairs!

    So the book must say add because the lines are on the example:

    2x+3y=13 A
    7x-5y=-1 B


    10x+15Y=65 C
    21x-15y=-3 D

    The book then says adding equations C + D Gives you

    31x=62

    I just want to make sure I'm reading what I'm reading, if you know what I mean
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    Remember if you add the equations, then you will get:

    23x + 12y = 59

    If you take the bottom one away from the top one, you will get:

    7x + 0y = 7

    7x = 7

    x = 7.


    It's jsut a silly mistake. If you remember to always think through it logically then you should be fine, but that's easier said than done. Good luck!

    TOO LATE
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    Thanks everyone, now I'm flying ahead x
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    yay! Well done :]
 
 
 
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