In the following figure, is a parallelogram whose two diagonals intersect at point , point , , intersects at point , and cm. Find .
Since the two diagonals of any parallelogram bisect each other and
point is the intersection of this parallelogram's diagonals,
we know that is a median of .
Since a triangle's point of intersection of medians divides each
median by the ratio of from the base and
, we know that point is the intersection point of the
medians of .
Since passes through point (the intersection
point of the medians), we know that is also a
median of .
Therefore, point bisects .