The figure below shows a right triangle ABC (angle B = 90 degree)
with the incircle I tangent to AC and BC at D and F, respectively. The excircle E corresponding to BC is
tangent to AB extended at G. Prove that D, F, and G are collinear points.

See also: Typography and poster of problem 1408.

Geometry Problems

Ten problems: 1401-1410

Visual Index

Open Problems

All Problems

Triangle

Circle

Incircle

Excircle

Tangent Line

Perpendicular lines

Collinear Points

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