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    Given the ellipses
    2𝑥2 + (𝑦 + 2)^2 = 18
    and
    16𝑥2 + 9(𝑦 − 1)^2 = 25,
    find the equation of the line which passes through their points of intersection
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    (Original post by ashv21)
    Given the ellipses
    2𝑥2 + (𝑦 + 2)^2 = 18
    and
    16𝑥2 + 9(𝑦 − 1)^2 = 25,
    find the equation of the line which passes through their points of intersection
    Are you missing variables or is it just my screen?

    Also, what have you tried?
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    Name:  image1 (2).JPG
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    (Original post by Kevin De Bruyne)
    Are you missing variables or is it just my screen?

    Also, what have you tried?
    This is the question. I tried solving it simultaneously using substitution but one of my answers was a complex number. I dont think it is correct
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    (Original post by ashv21)
    Name:  image1 (2).JPG
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    This is the question. I tried solving it simultaneously using substitution but one of my answers was a complex number. I dont think it is correct
    Please post your working
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    have you multiplied the top equation by 8 and subtracted both equations with each other? Work out the quadratic from there? And you get a complex number?
    If this is part of an entire question progression, please post the entire question ie parts a and b prior to part c.

    I'm in bed 😂😂😂 can't do this in my head unfortunately.
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    (Original post by Kevin De Bruyne)
    Please post your working
    Attachment 695626695628
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    (Original post by fp1washard)
    have you multiplied the top equation by 8 and subtracted both equations with each other? Work out the quadratic from there? And you get a complex number?
    If this is part of an entire question progression, please post the entire question ie parts a and b prior to part c.

    I'm in bed 😂😂😂 can't do this in my head unfortunately.
    This is the whole question. Once of the answers is a complex number!
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    What part of maths are you on. AS or A2
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    (Original post by Appleorpear)
    What part of maths are you on. AS or A2
    A2
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    before you get ur quadratic equation, 112-16 is 96, not -96

    Wait im still working on it, i see ur quadratic equation itself is right
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    (Original post by fp1washard)
    before you get ur quadratic equation, 112-16 is 96, not -96

    Wait im still working on it, i see ur quadratic equation itself is right
    got the answer, the line of intersection is y=2
    when u substitute y=2 into one of ur equations u need to square root both sides to get 1, when u square root, u get a plus or minus 1... hence there are two real solutions.
    Since the points are (1,2) and (-1,2) the line of intersection is y=2
 
 
 
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