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C1 curve intersection question please help watch

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    Would you please help me to see whether i'm tackling this problem in the right way?


    It says: Find the coordinates of the points of intersection of the curve y=(x-4)^2-3 with the x-axis and the y-axis, using surds when necessary. [4]


    So I made x = 0 and then said:
    y=(-4)^2 - 3
    y=16-3
    y=13
    => the coordinates of the point of intersection of the curve with the y axis are (0,13)


    then I made y=0 and formed a quadratic to find X
    x^2 -8x + 13 = 0


    I ended up with 4 +/- 2sqrt3


    so I said coordinates of intersection with the xaxis = (4 + 2 sqrt3, 0)
    or x = (4 - 2sqrt3, 0)


    would this get me all 4 marks?
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    (Original post by wednesday_adams)
    Would you please help me to see whether i'm tackling this problem in the right way?


    It says: Find the coordinates of the points of intersection of the curve y=(x-4)^2-3 with the x-axis and the y-axis, using surds when necessary. [4]


    So I made x = 0 and then said:
    y=(-4)^2 - 3
    y=16-3
    y=13
    => the coordinates of the point of intersection of the curve with the y axis are (0,13)


    then I made y=0 and formed a quadratic to find X
    x^2 -8x + 13 = 0


    I ended up with 4 +/- 2sqrt3


    so I said coordinates of intersection with the xaxis = (4 + 2 sqrt3, 0)
    or x = (4 - 2sqrt3, 0)


    would this get me all 4 marks?
    Absolutely spot on.
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    (Original post by wednesday_adams)
    Would you please help me to see whether i'm tackling this problem in the right way?


    It says: Find the coordinates of the points of intersection of the curve y=(x-4)^2-3 with the x-axis and the y-axis, using surds when necessary. [4]


    So I made x = 0 and then said:
    y=(-4)^2 - 3
    y=16-3
    y=13
    => the coordinates of the point of intersection of the curve with the y axis are (0,13)


    then I made y=0 and formed a quadratic to find X
    x^2 -8x + 13 = 0


    I ended up with 4 +/- 2sqrt3


    so I said coordinates of intersection with the xaxis = (4 + 2 sqrt3, 0)
    or x = (4 - 2sqrt3, 0)


    would this get me all 4 marks?

    The answers for x are incorrect
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    (Original post by wednesday_adams)
    Would you please help me to see whether i'm tackling this problem in the right way?

    I ended up with 4 +/- 2sqrt3
    x should = 4+/- sqrt3 not 4+/- 2sqrt3

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