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    If anyone could be kind enough to explain this to me i would be much obliged.

    AB is a chord of a circle and is 8cm long.

    The centre, O, is 6cm from the mid-point of AB.

    Calculate the length of the diameter of the circle.
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    Construct a triangle and find the hypotenuse by Pythagoras. That's your radius then double it to get the diameter.
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    (Original post by Riddle2001)
    If anyone could be kind enough to explain this to me i would be much obliged.

    AB is a chord of a circle and is 8cm long.

    The centre, O, is 6cm from the mid-point of AB.

    Calculate the length of the diameter of the circle.
    Is there anyway you could use a diagram to show the lengths you know which might help you find relevant info
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    (Original post by Riddle2001)
    If anyone could be kind enough to explain this to me i would be much obliged.

    AB is a chord of a circle and is 8cm long.

    The centre, O, is 6cm from the mid-point of AB.

    Calculate the length of the diameter of the circle.
    sketch sketch sketch, it'll be obvious once you've drawn it
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    (Original post by Riddle2001)
    If anyone could be kind enough to explain this to me i would be much obliged.

    AB is a chord of a circle and is 8cm long.

    The centre, O, is 6cm from the mid-point of AB.

    Calculate the length of the diameter of the circle.
    Let the midpoint be M, so AM=4 and MO=6. Clearly angle AMO is a right angle. Thus by Pythagoras, AO=sqrt(16+36)=2sqrt(13). Thus the radius is 2root13, so the diameter is 4root13.
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    (Original post by Riddle2001)
    If anyone could be kind enough to explain this to me i would be much obliged.

    AB is a chord of a circle and is 8cm long.

    The centre, O, is 6cm from the mid-point of AB.

    Calculate the length of the diameter of the circle.
    Lamo. Just make a triangle and use the formula A^2+B^2=C^2, that'll be your radius*2=diameter (this step tends to get allot easier when you have a diagram infront of you). The final step is to get high on potnuse.
 
 
 
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