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Homework Help: Geometry proofs.

  1. Apr 28, 2010 #1
    I need help in how to do this proof.

    A circle is given with diameter AB. pick any point C on the circle and drop a perpendicular from C to the given diameter at D. Find CD in terms of AD and BD.
  2. jcsd
  3. Apr 28, 2010 #2


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    Connect C to A and to B. What kind of triangle is triangle ABC?
  4. Apr 28, 2010 #3
    An easier way: Let O be the centre of the circle. Then OC = OA = (AD+BD)/2. Then look at the triangle ODC to find the answer.
  5. Oct 28, 2011 #4
    I understand upto where you have reached but I still cant proceed from there
  6. Oct 28, 2011 #5
    all sides are unequal
  7. Oct 28, 2011 #6


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    What do you know about angle ACB?
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