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1. Here is the question:

a) I don't know how you would find the radius from the given equation. Can you please explain it to me and walk me through?
b) I don't know how I would find the radius. The only equation I know to do with this (idk if it helps) is (x-a)^2 + (y-b)^2 = r^2. How do you do a question like this? Please can you help?
c) Normally, I know that something crosses the x axis when y=0, but how do I do that here? How do I know which equation to put y=0 as?
d) I have no clue with this one.

I would especially like help with a b and c please. Can you please walk me through, and explain why you do each step, and what each step actually is?

Thank you!
2. (Original post by blobbybill)
Here is the question:

a) I know this is (5,0).
b) I don't know how I would find the radius. The only equation I know to do with this (idk if it helps) is (x-a)^2 + (y-b)^2 = r^2. How do you do a question like this? Please can you help?
c) Normally, I know that something crosses the x axis when y=0, but how do I do that here? How do I know which equation to put y=0 as?
d) I have no clue with this one.

I would especially like help with b and c please. Can you please walk me through, and explain why you do each step, and what each step actually is?

Thank you!
Yes you need to get it in the form .

To do this you need to complete the square for the x terms and y terms separately. So for the x terms you can do

Can you try the same for the y terms then join it all together?

This is a common method in exam questions that you need to get used to.

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