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    I'm stuck on a question about ellipses.
    I've got an equation of an ellipse:

    x^2/9 + y^2/25 = 1

    Find the possible values of m for which the line y=mx+6 intersects the ellipse.
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    Anyone?
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    I'm unsure if it is necessary, but I'd rewrite them to begin:

    (x/3)^2 + (y/5)^2 = 1
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    (Original post by NeeIam)
    Anyone?
    I am slightly confused (Perhaps because i've just got up) but you have the general equation of a line. Do you know what c is or not?
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    (Original post by zetamcfc)
    I am slightly confused (Perhaps because i've just got up) but you have the general equation of a line. Do you know what c is or not?
    Damn I should've proof read my initial post. The equation of the line is y=mx+6
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    (Original post by NeeIam)
    I'm stuck on a question about ellipses.
    I've got an equation of an ellipse:

    x^2/9 + y^2/25 = 1

    Find the possible values of m for which the line y=mx+6 intersects the ellipse.
    Easiest way to solve this is to draw the ellipse then use trial and error to find m.
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    (Original post by NeeIam)
    I'm stuck on a question about ellipses.
    I've got an equation of an ellipse:

    x^2/9 + y^2/25 = 1

    Find the possible values of m for which the line y=mx+6 intersects the ellipse.
    Rewrite as:
    (x/3)^2 + (y/5)^2 = 1

    You know that the line y=mx+6 intersects the ellipse which implies that they share coordinates at least once, so plug in y=mx+6 into the rewritten version of the ellipse and expand. Once fully expanded, plug in the relevant values into b^2 - 4ac and then you should get the answer - hopefully.
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    (Original post by RoseGatz)
    Rewrite as:
    (x/3)^2 + (y/5)^2 = 1

    You know that the line y=mx+6 intersects the ellipse which implies that they share coordinates at least once, so plug in y=mx+6 into the rewritten version of the ellipse and expand. Once fully expanded, plug in the relevant values into b^2 - 4ac and then you should get the answer - hopefully.
    Should it be b^2-4ac>0 ?
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    (Original post by NeeIam)
    Should it be b^2-4ac>0 ?
    Possibly... Do you know what the answer is supposed to be?
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    (Original post by RoseGatz)
    Possibly... Do you know what the answer is supposed to be?
    Nope but I'm working towards it
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    (Original post by NeeIam)
    Nope but I'm working towards it
    Is this an exam paper?
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    (Original post by zetamcfc)
    Is this an exam paper?
    No it's from a worksheet
 
 
 
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