All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars    
perplexus dot info

Home > Shapes > Geometry
Collinear intersections (Posted on 2009-07-13) Difficulty: 2 of 5
Two smaller circles of radii a and b are internally tangent to a larger circle, of radius r, at points P and Q respectively. The smaller circles intersect at points S and T.

If P, S, and Q are collinear, prove that r = a+b.

See The Solution Submitted by Bractals    
No Rating

Comments: ( Back to comment list | You must be logged in to post comments.)
re(2): proof Comment 3 of 3 |
(In reply to re: proof by Bractals)

Right: as all three triangles are similar, angle SBQ = angle PRQ and so BS is parallel to PAR.
  Posted by Charlie on 2009-07-14 02:34:14

Please log in:
Login:
Password:
Remember me:
Sign up! | Forgot password


Search:
Search body:
Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (2)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:
Copyright © 2002 - 2017 by Animus Pactum Consulting. All rights reserved. Privacy Information