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    Please could you help. Solve the simultaneous equations, giving your answers in their simplest form
    2x+3y=13
    x^2+y^2=78
    My attempt was poor. I realised 13 goes into 78 6 times so equated 6(2x+3y) with x^2+y^2 and expanded. I also found y and x from the equations and tried to sub them into the seconds one, however they gave awful fractions to deal with.
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    (Original post by MathMeister)
    ...
    Show attempt.
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    I definitely got it right. I just made a reaally stupid error. Herp derp. I thought -9-11=-19 whereas it equals -20, this was when I was completing the square. I've learnt loads from TSR. I'm getting back on track academically. Last time I posted loads of threads and got banned for it. Is there any way of deleting threads you started?
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    (Original post by MathMeister)
    Please could you help. Solve the simultaneous equations, giving your answers in their simplest form
    2x+3y=13
    x^2+y^2=78
    My attempt was poor. I realised 13 goes into 78 6 times so equated 6(2x+3y) with x^2+y^2 and expanded. I also found y and x from the equations and tried to sub them into the seconds one, however they gave awful fractions to deal with.
    2x = 13 - 3y

    4x^2 = (13-3y)^2

    x^2 = 78 - y^2

    Combine to get a quadratic in y
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    I perfectly understand now. Ahhh . prsom. Good working. I suppose it's good to think about something in different ways.
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    (Original post by MathMeister)
    I don't really understand, but the working seems better and more interesting that mine. prsom.
    What don't you understand?

    When you did simultaneous equations like this at GCSE what method(s) were you taught?
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    My mind really hasn't been working as sharply today. It's maybe because I' a tad tired.
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    (Original post by MathMeister)
    My mind really hasn't been working as sharply today. It's maybe because I' a tad tired.
    ok

    Are you happy with the method now?
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    Happy
 
 
 
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