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    Hi, I was wondering if anyone could help me on part of this question? Here's the information ive already been given/worked out: the points P (9,3) and Q (1,-3) lie at opposite ends of a circle - radius=5, centre= (5,0) equation of circle= (x-5)^2 + (y-0)^2 = 5^2
    Describe a geometrical transformation by which C can be obtained from the circle with the equation x^2 + y^2 = r^2
    I don't really get this...is it just 5^2 - 0^2 = 5^2? I don't get what I'm supposed to be writing
    Thanks in advance!
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    Are you sure that it is

    x^2 + y^2 = r^2
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    Do you know what transformation is needed to go from f(x) to f(x-5)
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    (Original post by TenOfThem)
    Do you know what transformation is needed to go from f(x) to f(x-5)
    in regards to your first post, yes it definitely says in the question: describe the geometrical transformation by which C can be obtained from the circle with the equation x^2 +y^2= r^2

    and yeah, that would be a translation by vector (5,0) right?
    is that what it is, because thats the coordinates of the centre? not sure how to use x^2 +y^2= r^2 with it though
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    So, to go from x^2 + y^2 = 5^2

    to (x-5)^2 + y^2 = 5^2

    would be a translation as you say

    How might you transform a circle radius = 1 to a circle radius = 5
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    (Original post by TenOfThem)
    So, to go from x^2 + y^2 = 5^2

    to (x-5)^2 + y^2 = 5^2

    would be a translation as you say

    How might you transform a circle radius = 1 to a circle radius = 5
    ermmmmmmm an enlargement? scale factor 5? thats a complete guess aha:/

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Updated: March 26, 2012
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