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Dat circle geo (1 Viewer)

andrew29223

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Draw a tangent through the point of intersection, then use angle in alternate segment theorem and vertically opposite angles (angles between the line you are given and your tangent) and prove the two alternate angles are equal therefore must be collinear
 

lulwut

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if you did alternate angles from the tangent drawn between the two circles, the proof would be valid right? you're proving that both angles produced from the tangent to their respective lines are equal -> therefore lies on the same line / co-linear.. I think..
 

RealiseNothing

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Draw a tangent through the point of intersection, then use angle in alternate segment theorem and vertically opposite angles (angles between the line you are given and your tangent) and prove the two alternate angles are equal therefore must be collinear
This is what I did.
 

lulwut

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Draw a tangent through the point of intersection, then use angle in alternate segment theorem and vertically opposite angles (angles between the line you are given and your tangent) and prove the two alternate angles are equal therefore must be collinear
I'm always late to the party :'(
 

RealiseNothing

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if you did alternate angles from the tangent drawn between the two circles, the proof would be valid right? you're proving that both angles produced from the tangent to their respective lines are equal -> therefore lies on the same line / co-linear.. I think..
I think that's fine.
 

panda15

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Draw a tangent through the point of intersection, then use angle in alternate segment theorem and vertically opposite angles (angles between the line you are given and your tangent) and prove the two alternate angles are equal therefore must be collinear
I did this. Glad I'm not the only one.
 

ninasandwich

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yeah... I think I screwed this question up completely- I might scab a mark for it but- I saw I couldn't assume so I forgot about that proof, and instead went with the one that claims "any 3 non-collinear points are con-cyclical points" , then stated as point T is the point of intersection, a line drawn between the centres of the circles passes through T. Therefore since 'Q' and 'P' are points on the circumference of their respective circles, the three points cannot form a circle, and therefore must be collinear. hahah I hope they give me mark for trying:mad2:
 

RealiseNothing

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Hey iBibah, doesn't it remind you of the UNSW seminar back in January.

Where like EVERYONE, including the 3rd year maths students, assumed it was a straight line.

de ja vu
 

seanieg89

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Hey iBibah, doesn't it remind you of the UNSW seminar back in January.

Where like EVERYONE, including the 3rd year maths students, assumed it was a straight line.

de ja vu
Lol, that's why you should choose usyd ;).
 

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