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# Circles help

1. 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!
2. Are you sure that it is

3. Do you know what transformation is needed to go from f(x) to f(x-5)
4. (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
5. So, to go from

to

would be a translation as you say

How might you transform a circle radius = 1 to a circle radius = 5
6. (Original post by TenOfThem)
So, to go from

to

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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