How can you plant seven straight rows of trees with six trees per row such that twenty-one trees are planted in total?

How can you plant nine straight rows of trees with three trees per row such that nine trees are planted in total?

(In reply to part 1 by Charlie)

This is somewhat reminiscent of JLo's Cutting Planes with Polygons.

We simply have to have all 7 lines intersect with every other one ensuring that only two lines intersect at a point.

Posted by brianjn on 2006-10-21 21:51:01