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Online Math: Geometry Problem 1220: Equilateral Triangles, Midpoints, 60 Degrees, Congruence. Tiled background image: Intihuatana, Machu Picchu. Level: College, High School.

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In the figure below, equilateral triangles ABC1 and A1BC are drawn on the sides of a triangle ABC. If D, E, and F are the midpoints of BC, AB, and A1C1, respectively, prove that the triangle DEF is equilateral.
 
 

Geometry Problem 1220: Scalene Triangle, Equilateral Triangles, Midpoints, 60 Degrees, Congruence.
 
 

 

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Home | SearchGeometry | Problems | All Problems | Open Problems | Visual Index | 10 Problems | Problems Art Gallery Art  | 1211-1220 | Triangles | Equilateral triangle | Midpoint | Congruence | 60 degrees | Email | by Antonio Gutierrez

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Last updated: Jun 1, 2016