Centroid and medians in Triangle

Centroid:

1. 3 Medians divide triangle in 6 equal parts. Proof.
2. 3 Medians are concurrent and centroid divides median in 2:1. Proof.
3. How do 2 medians divide triangle? Relation between areas? Use 1. to come up with this relation. 4 areas in 2:1.
4. Centroid is always inside the triangle.

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