Show that (1/3 [2x1 + x2], 1/3[2y1+y2]) is one of the points of trisection of the line segment joining (x1,y1) and (x2,y2). Then find the second point of trisection by finding the midpoint of the segment joining

(1/3[2x1 + x2], 1/3[2y1 + y2]) and (x2, y2)

Use exercise 28 to find the points of trisection of the line segment joining the given points.

a (1 , -2) (4, -1)

b. (-2, -3) (0,0)