The circumcentre of a triangle lies at the origin and the centroid is the midpoint of the line segment joining the points and , then the orthocentre lies on the line.
We know that, circumcentre, centroid and orthocentre of a triangle are collinear.
Hence, orthocentre lies on the line joining circumcentre (0, 0) and centroid
Equation of the line is
Therefore, the equation of the line where the orthocentre lies is