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    I'm having difficulty with the following question:

    Solve the simultaneous equations
     4x^2 + y^2 = 10
     2x - y = 4

    The elimination method doesn't seem to work at all, and when I use the substitution method I get difficult numbers like  8x^2 = -6 or  3y^2 = -22 which can't be right. Any idea where I might be going wrong?

    Thanks in advance,

    Digichris.
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    (Original post by Digichris)
    I'm having difficulty with the following question:

    Solve the simultaneous equations
     4x^2 + y^2 = 10
     2x - y = 4

    The elimination method doesn't seem to work at all, and when I use the substitution method I get difficult numbers like  8x^2 = -6 or  3y^2 = -22 which can't be right. Any idea where I might be going wrong?

    Thanks in advance,

    Digichris.
    Rearrange the second equation to make either x or y the subject, square it and sub it into the first equation to get either x or y. Once you know one variable, you can sub it back into the second equation to get the other.

    EDIT: you should get 2 sets of x and y values, with each x value having a corresponding y value.
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    show that y = 2x - 4, then sub that in the equation with 4x^2.....etc, get the value(s) for x then value(s) for y
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    Heh, thank you. I just realised I was making a stupid mistake xD
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    (Original post by Digichris)
    Heh, thank you. I just realised I was making a stupid mistake xD
    cool
 
 
 
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