# Typography of Geometry Problem 1408: Right Triangle, Incircle, Excircle, Incenter,
Midpoint,
Tangency Point, Collinearity, iPad Apps

### Proposition

The figure below shows a right triangle ABC (angle B = 90 degree). The excircle E corresponding to BC is
tangent to BC at F. If I is the incenter and D is the midpoint of AB, prove that D,
I,
and F are collinear points.

### Geometric Art using iPad or Mobile Apps

Geometric art is a form of art based on the use and application of geometric figures. A geometric figure is any set or combination of points, lines, surfaces and solids.

A mobile app or mobile application software is a computer program designed to run on smartphones and tablet computers.

See also:

Original problem
1408.

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