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It has become obvious that the Shapes category was in way over its head with all sorts of geometrical problems. So, the hard-core Geometry problems will now reside here, where they will fit in much better.
I is the incenter of triangle ABC with
B' the intersection of the ray BI and
side AC and C' the intersection of ray
CI and side AB.
Prove that AB'IC' is a cyclic quadrilateral if and only if angle BAC is 60 degrees.
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A unique Heronian triangle
Posted on 2017-08-05 by (No Solution Yet, 6 Comments) Jer Two parallelograms
Rating: 3.00 Posted on 2017-08-01 by (No Solution Yet, 3 Comments) Ady TZIDON Heronian with consecutives
Rating: 3.00 Posted on 2017-07-29 by (No Solution Yet, 1 Comments) Jer Pruned Triangle
Posted on 2017-07-28 by (Solution Posted, 1 Comments) Bractals Regular N-gon
Rating: 4.00 Posted on 2017-07-09 by (No Solution Yet, 2 Comments) Bractals Lewis Carroll's finding
Posted on 2017-06-25 by (No Solution Yet, 1 Comments) Ady TZIDON Pythagoras' corner
Posted on 2017-06-16 by (No Solution Yet, 3 Comments) Jer Delian delight
Posted on 2017-06-04 by (No Solution Yet, 3 Comments) Jer Add one more circle
Posted on 2017-05-21 by (No Solution Yet, 5 Comments) Brian Smith The length of the belt
Rating: 3.00 Posted on 2017-05-09 by (No Solution Yet, 5 Comments) Ady TZIDON Many equal shapes
Posted on 2017-04-30 by (No Solution Yet, 0 Comments) Jer Is it a conic?
Rating: 4.00 Posted on 2017-04-19 by (No Solution Yet, 7 Comments) Jer Polygon Overlap
Posted on 2017-04-17 by (No Solution Yet, 1 Comments) Bractals Three heights in a triangle
Posted on 2017-03-11 by (No Solution Yet, 2 Comments) Ady TZIDON
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