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).

If the line joining the points A(2,3,-1) and B(3,5,-3) is perpendicular to the line joining the points C(1,2,3) and D(3,y,7) then y=

Show that the line joining the points (2,-6) and (-4,-8) is perpendicular to the line joining the points (4,-2) and (6,-8) .

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 joining the points (4,-3) and (0,7) is perpendicular to the line joining the points (5,2) and (0,0) .

Determine the value of k so that the line joining points A(k,1,-1) and B(2,0,2k) is perpendicular to the line joining the points C(4,2k,1) and D(2,3,2) .

Line joining the points (3,-4) and (-2,6) is perpendicular to the line joining the points (-3,6) and (9,-18).

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).