Triangles by folding paper

1. Take the piece of paper in your hands and fold it along an imaginary line.(Any line is OK).
2. Cross the previous line by folding the paper following another imaginary line.
3. Fold the paper along a third line, to make a triangle.
4. Unfold the paper and try to make the lines very clear and sharp.
5. Tear the paper carefully, along the lines you have made.
6. Now we have a triangle!
7. Hold the triangle in your hands and try to find the middle point of one side by joining the vertices of that side.
8. Fold the paper along the line that joins the middle point to the opposite vertex. That is the median of one side.
9. Repeat the last two steps to make the other two medians of the triangle.
10. The point where the lines cross is called the centroid or barycenter.