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measuring lines from a tangent in a circle CCEA C2 watch

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    In this question you have to find the area of thr kit. When finding the length of side AC. BC is taken to be 5. After using calculations i get the radius to be 4 and cannot understand why the length used is 5. Point C also has coordinates of (3,-5) using the circle equation to work it out. The radius is also 4 on the markscheme but 5 is still used as the lengthbof BC can someone help me out? Thanks
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    I think that's how you do it, didn't check over it but I think it's right? What did you get?
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    (Original post by GlitchKid)
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    In this question you have to find the area of thr kit. When finding the length of side AC. BC is taken to be 5. After using calculations i get the radius to be 4 and cannot understand why the length used is 5. Point C also has coordinates of (3,-5) using the circle equation to work it out. The radius is also 4 on the markscheme but 5 is still used as the lengthbof BC can someone help me out? Thanks
    Might be a mistake? I got BC to be 4 too.
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    No those are the same answers as the mark scheme, but why do you take BC to be 5 and not 4 in your triangle? I can see how (by making a triangle out of both coords) but then the triangle doesn't make since as BC must be 4 as it is radius but to find AC you take it to be 5
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    (Original post by GlitchKid)
    No those are the same answers as the mark scheme, but why do you take BC to be 5 and not 4 in your triangle? I can see how (by making a triangle out of both coords) but then the triangle doesn't make since as BC must be 4 as it is radius but to find AC you take it to be 5

    Is that what you mean? The 5 was from the coordinates of the centre point. To work out length of AC, you don't need the length of BC.
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    Yes so then you arent using the triangle given you are creating your own with the corordinates given?
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    (Original post by GlitchKid)
    Yes so then you arent using the triangle given you are creating your own with the corordinates given?
    To find out the length of AC, I create a new triangle to find out that length. Then once I've got AC, and I have BC already so I can find out AC, then find out the area of the triangle they are asking for. Hope that makes sense.
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    Yea thats akriggt i understand it now, thanks
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    (Original post by GlitchKid)
    Yea thats akriggt i understand it now, thanks
    No problem, feel free to give me +Rep if I helped
 
 
 
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