Prove that the straight line joining the points A(4, -3, 2) and B(2, -1, -1) is parallel to the straight line joining the point C(7, -3, 5) and D(1, 3, -4).

Prove that the straight line joining the points (4, 5, 0) and (5, 3, 3) is parallel to the straight line joining the point (4, 3, -3) and (6, -1, 3).

If the straight line joining the points A(3, 4, -1) and B(4, p, 2) is parallel to the straight line joining the points C(2, 1, q) and D(4, -3, 1), then -

The straight line joining the points (-3,-4) and(2,5) is -

If the straight line joining the points (4, -3, 2) and (3, -1, 5) is perpendicular to the straight line joining the points (m, -2, 1) and (7, 3, -2), then the value of m is -

The straight line joining the points (3,-5 ) and (-3,-5) is parallel to the -

Show that the staright line joining the points (-1, 0, -2) and (1, 3, -1) is perpendicular to the straight line joining the points (9, 1, -6) and (7, 2, -5)

Determine the values of a and b for which the straight line joining the points (7, 4, 2) and (3, -2, 5) may be parallel to the line joining the points (2, a, 5) and (b, -15, 11).

If the straight line joining the points (3,4) and (2,-1) be parallel to the line joining the points (a,-2) and (4,-a), find the value of a.

Show that the straight line joining the points (-3,2) and (6,-4) passes through the origin .

Show that the straight line joining the points (4,-3) and (-8,6) passes through the origin .