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    x²+y²=17
    3y+x=11


    help solving this plsssssss
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    Rearrange the second one for x or y, x is easier, and then sub into first one and solve for y. And, haven't you already posted this?
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    x = 11 - 3y

    (11 - 3y)² + y² = 17

    6y² - 66y + 121 + y² = 17

    7y² - 66y + 104 = 0

    Complete square/use formula


    hope i havent made a mistake there, the numbers are a bit gay in the quadratic
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    rearrange 3y+x=11, into x=11-3y
    and substitute so (11-3y)^2 +y^2=17, multiply brackets out, simplify, and form a quadratic, obtain 2 y values, then substitute them both into x=11-3y, to obtain 2 x values
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    should be 9y^2 not 6y^2 zd000
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    (Original post by nathsen)
    should be 9y^2 not 6y^2 zd000
    haha knew i did something stupid in there xD
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    If you're looking for academic help, please post in the relevant academic help forum rather than the general secondary one .
 
 
 
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