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triangle fold

This is a triangle folding activity. A and B are movable points. You can make a fold by dragging point C. Turn off the grid if needed. What tasks or questions will you try for exploring properties of a triangle?
How about trying these:
  • make a fold to:
bisect angle A; angle B bisect side BC; AC add the altitude from A; from B
  • does the angle bisector of A bisect BC? when?
  • show that longer side is opposite to greater angle
  • cover point A, drag B to make angles B and C almost equal, fold C to B and compare the angles in order to tell which opposite side is longer