Prove by vector method that the medians of a triangle are concurrent.

Prove the following by vector method. Altitudes of a triangle are concurrent.

Prove by vector method that the diagonals of a quadrilateral bisect each other iff is a parallelogram.

Prove by vector method that the diagonals of a parallelogram bisect each other.

Prove analytically : The perpendicular bisector of the sides of a triangle are concurrent.

Prove by vector method that the mid-point of the hypotentise of a right angles triangle is equidistance from the vertices.

Prove by vector method that in any triangle ABC, the point P being on the side vec(BC) , if vec(PQ) is the resultant of the vectors vec(AP) , vec(PB) and vec(PC) , then ABQC is a parallelogram.

Prove by vector method that the lines joining the mid points of consecutive sides of a quadrilateral is a parallelogram.

Prove by vector method that the line segment joining the mid points of two sides of a triangle is parallel to the third and half of it.