Official solution
Let the centroid of \[\Delta \]PQR is (h, k) \& P is (\[\alpha \], \[\beta \]), then
\[{{\alpha + 1 + 3} \over 3} = h\,\] and \[{{\beta + 4 - 2} \over 3} = k\]
\[\alpha = \left( {3h - 4} \right)\] \[\beta = \left( {3k - 4} \right)\]
Point P(\[\alpha \], \[\beta \]) lies on the line 2x - 3y + 4 = 0
\[ \therefore \] 2(3h - 4) - 3 (3k - 2) + 4 = 0
\[ \Rightarrow \] locus is 6x - 9y + 2 = 0