Show that the line through the points `(1, 1, 2), (3, 4, 2)`is perpendicular to the line through the points (0, 3, 2) and (3, 5, 6).

Show that the line through the points : (a) (1, -1, 2), (3,4,-2) is perpendicular to the line through the points (0,3,2) and (3, 5,6) (b) (4,7,8) , (2,3,4) is parallel to the line through the points (-1, -2, 1 ) and (1,2,5) .

Show that the line through the points (1, -1, 2) and (3, 4,-2) is perpendicular to the through the points (0, 3,2) and (3, 5, 6).

Show that the line through the points (1,-1,2) and (3,4-2) is perpendicular to the line through the points (0,3,2) and (3,5,6).

Show that the line thorugh the points (1,-1,2) and (3,4,-2) is perpendicular to the line through the points (0,3,2)andf (3,5,6).

Show that the line through the points (-2, 6) and (4, 8) is perpendicular to the line through the points (3,-3) and (5,-9).

Show that the line through the points (-2,6) and (1,7) is perpendicular to the line through the points (3,-3) and (5,-9).

Show that the line joining the point A(1,-1,2) and B(3, 4, -2) is perpendicular to the line joining the points C(0,3,2) and D(3,5,6).

Show that the line through the point (4, 7, 8) and (2, 3, 4) is parallel to the line through the points (-1, -2, 1) and (1, 2, 5).

Find the value of p for which the line through the points A(4,1,2) and B(5,p,0) is perpendicular to the line through the points C(2,1,1) and D(3,3,-1) .

Show that the line through the points (4,7,8),(2,3,4) is parallel to the line through the points (-1,-2,1) (1,2,5)