Question 923811
r the number of rows. (r+6) plants in each row.
r(r+6) = 432
r^2 + 6r - 432 = 0 Factor
(r + 24)(r - 18) = 0  (tossing out negative solution for unit measure)
r = 18, the number of rows.  24 plants in each row {{{18+6}}}