- #1

DotKite

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## Homework Statement

In triangle ABC, AB = AC, and D,E,F are points on the interiors of sides BC,AB,AC respectively, such that DE perpendicular to AB and DF perpendicular to AC. Prove that the value of DE + DF is independent of the location of D

## Homework Equations

So far we have all the tools of neutral geometry and non neutral parallelism. We have not covered similarity yet

## The Attempt at a Solution

Ok so I guess a good approach would be to consider triangle ABC with D in one location and then another and show there is no change in DE + DF. However I do not have a clue in how to proceed with this. Tried using the fact that triangle ABC is isosceles therefore the base angles are equal, but don't really know where to go with that either