Quote:
Originally Posted by PRERANA MITRA
If Vertices of a triangle are {0,0},{3,0}and{3,3} then find its orthocentre?

The orthocenter of a triangle occurs at the point where the three altitudes of the triangle intersect. According to the vertices you have given for the triangle, the triangle is a right triangle. Therefore, the three altitudes intersect at (3,0). So the orthocenter is (3,0).