Geometry Problem 1459: Two Triangles, Orthocenter, Midpoint, Perpendicular

The figure shows the vertical angles BAC and DAE. F and G are the orthocenters of trianglers ABC and ADE, respectively. If M and N are the midpoints of BE and CD, respectively, prove that MN and FG are perpendicular.

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Static Diagram of problem 1459

Dynamic Geometry 1459: Two Triangles, Orthocenter, Midpoint, Perpendicular, Step-by-step Illustration. Using GeoGebra

Poster of the problem 1459 using iPad Apps

Poster of Problem 1459, Two Triangles, Orthocenter, Midpoint, Perpendicular, Step-by-step Illustration, GeoGebra, iPad


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