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    Can someone please solve this for me;

    I am looking for the intersecting points of the following lines,

    y=x (straight line from bottom left to top right)

    and

    y= 2x squared (u shaped curve)

    i know they intersect at (0,0) but how do i find the other point of intersection?
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    make the 2 equations equal to eachother

    x=2x^2

    then rearrange to get

    2x^2 - x =0

    then factorise

    x(2x-1)=0

    therefore

    x=0 and 2x-1=0 therefore getting x=1/2


    then substitute thes x co orsinates into ony of the equations to get the y co ordinates ( which you will get y=0 and y=1/2)
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    I think the objective here is not to tell them the answer jahan. But to....guide them
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    I think people need to read the posting guidelines: http://www.thestudentroom.co.uk/showthread.php?t=403989
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    yeah sorry about that! just try out some similar examples which there will be many
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    (Original post by jahan218)
    make the 2 equations equal to eachother

    x=2x^2

    then rearrange to get

    2x^2 - x =0

    then factorise

    x(2x-1)=0

    therefore

    x=0 and 2x-1=0 therefore getting x=1/2


    then substitute thes x co orsinates into ony of the equations to get the y co ordinates ( which you will get y=0 and y=1/2)

    where does the -1 come from?

    also how can x=0 and 2x-1 =0 equate to 0.5?
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    (Original post by dantheram)
    where does the -1 come from?
    Factorizing the LHS.

    also how can x=0 and 2x-1 =0 equate to 0.5?
    He meant to say x=0 or 2x-1=0. So x=0 or x=1/2.
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    (Original post by dantheram)
    Can someone please solve this for me;

    I am looking for the intersecting points of the following lines,

    y=x (straight line from bottom left to top right)

    and

    y= 2x squared (u shaped curve)

    i know they intersect at (0,0) but how do i find the other point of intersection?
    You can also solve it graphically and must if the question says to do it that way.
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    (Original post by stevencarrwork)
    You can also solve it graphically and must if the question says to do it that way.
    i don't see how if you're drawing it you're going to be absolutely sure of getting the right point.

    how do you know it's not 0.500000000000000000000000000001 if you're drawing it?
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    (Original post by Totally Tom)
    i don't see how if you're drawing it you're going to be absolutely sure of getting the right point.

    how do you know it's not 0.500000000000000000000000000001 if you're drawing it?
    But this is still required sometimes, at least in GCSE maths.
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    (Original post by BJack)
    Factorizing the LHS.



    He meant to say x=0 or 2x-1=0. So x=0 or x=1/2.

    yeah thats what i meant, your just reading it the wrong way (which is my fault since there is no punctuation in it)
 
 
 
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