In triangle ABC, base BC and area of triangle ′Δ′ are fixed. Locus of the centroid of triangle ABC is a straight line that is
parallel to side BC
Δ=12(BC)h,where 'h' is the distance of vertex 'A' from side BC.ΔGBC=Δ3=(BC)h6,where 'G' is centroid.⇒h=2Δ(BC)=constantThus distance of vertex 'A' from side is fixed. This implies that distance of centroid from side BC will be fixed, hence locus of 'G' will be a line parallel to BC.