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    A Circle C1 has equation x^2+y^2-12x+4y+20=0
    A) find coordinates of the centre of C1
    B) find the radius of C1

    The circle C1 cuts the x-axis at the points A and B
    C) find an equation of the circle C2 with diameter AB

    Please help, I'm so confused 😔
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    (Original post by xALMOSTxPERFECTx)
    A Circle C1 has equation x^2+y^2-12x+4y+20=0
    A) find coordinates of the centre of C1
    B) find the radius of C1

    The circle C1 cuts the x-axis at the points A and B
    C) find an equation of the circle C2 with diameter AB

    Please help, I'm so confused 😔
    What is the centre of a circle with equation (x-a)^2 + (y-b)^2 = r^2?
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    (Original post by SeanFM)
    What is the centre of a circle with equation (x-a)^2 + (y-b)^2 = r^2?
    Umm I don't know?? :/
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    (Original post by xALMOSTxPERFECTx)
    Umm I don't know?? :/
    Refer to your notes.
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    (Original post by RDKGames)
    Refer to your notes.
    I don't have any that's the problem, hence why I've asked for help
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    (Original post by xALMOSTxPERFECTx)
    I don't have any that's the problem, hence why I've asked for help
    Have you covered this topic then?
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    (Original post by xALMOSTxPERFECTx)
    Umm I don't know?? :/
    Check your textbook, I think it would be best to revise the content first before coming back to the questikn
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    (Original post by RDKGames)
    Have you covered this topic then?
    No I haven't. Teacher gave it to us to try it out, I have no idea what I'm doing. The textbook isn't helping me because it hasn't got any of the same questions in it
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    (Original post by xALMOSTxPERFECTx)
    No I haven't. Teacher gave it to us to try it out, I have no idea what I'm doing. The textbook isn't helping me because it hasn't got any of the same questions in it
    You should look at the content first.

    A circle in the form (x-a)^2+(y-b)^2=c^2 has radius c with centre coordinates (a,b)

    To complete the first question you need to complete the square on x and y and get the equation into the general form before determining the centre and radius. Look at the content for more information.
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    (Original post by RDKGames)
    You should look at the content first.

    A circle in the form (x-a)^2+(y-b)^2=c^2 has radius c with centre coordinates (a,b)

    To complete the first question you need to complete the square on x and y and get the equation into the general form before determining the centre and radius. Look at the content for more information.
    Thank you, I'll try that but I still think I'm confused
 
 
 
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