Geometry Problem 1412: Right Triangle, Incircle, Excircle, Tangency Points, 45 Degree Angle

Proposition

The figure below shows a right triangle ABC (angle B = 90 degree) with the incircle I tangent to AB and AC at D and G, respectively. The excircle E corresponding to BC is tangent to BC at F. Prove that the measure of the angle FDG is 45 degree.
 

 

Geometry Problem 1412: Right Triangle, Incircle, Excircle, Tangency Points, 45 Degree Angle, Tutor




Poster of Problem 1412: Sketching, iPad, Typography, Art

Poster of Geometry Problem 1412: Right Triangle, Incircle, Excircle, Tangency Points, 45 Degree Angle, Sketching, iPad, Typography, Art, SW, Tutor

 

See also: Typography and poster of problem 1408.

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