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    Hey guys Can someone help me resolve the parametric equation I just find it practically impossible

    x=t^2+t
    y+t^2-t

    I always seem to be having an extra t and I can't get rid of it what so ever.
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    (Original post by ChemBoy1)
    Hey guys Can someone help me resolve the parametric equation I just find it practically impossible

    x=t^2+t
    y+t^2-t

    I always seem to be having an extra t and I can't get rid of it what so ever.
    Have u written the second one correctly?
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    if x = t2 + t

    y = t2 - t

    if you subtract them you can find an expressions for t involving x and y. then put this back into either of the two wherever it says t.
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    Sorry, I don't quite follow, if I subtract y -x I will get -2t. What should I do from there, the question wants me to plot it, and I we can't use graphical calculator, so If I could convert it into a Cartesian one, I could just put out a table of values.
    (Original post by the bear)
    if x = t2 + t

    y = t2 - t

    if you subtract them you can find an expressions for t involving x and y. then put this back into either of the two wherever it says t.
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    (Original post by ChemBoy1)
    Sorry, I don't quite follow, if I subtract y -x I will get -2t. What should I do from there, the question wants me to plot it, and I we can't use graphical calculator, so If I could convert it into a Cartesian one, I could just put out a table of values.
    you could choose values of t and work out x and y for each value ?
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    I presume you mean:

    -  x = t^{2} + t,

    -  y =  t^{2} - t,

    (where the bold is my correction),

    as you could find "x+y" and "x-y" to find terms with "t".
    Then try to link expressions involving "x+y" and "x-y" together.

    ----------------------------------------------------------------------------------------

    If you just need to plot a graph, then as "thebear" suggested, why not just pick values of t to find x and y?

    Also, the cartesian form does not appear simple enough for simple plotting anyway.

    Spoiler:
    Show

    A parabola rotated and shifted?
 
 
 
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