Show that the line joining (2, -3) and (- 5,1) is :
perpendicular to the line joining (4, 5) and (0, - 2).

Show that the line : through (2, - 3) and (-1, 2) is perpendicular to the line joining (3, 7) and (- 2, 4).

Show that the line joining (2,-3) and (-5,1) is parallel to the line joining (7,-1) and (0,3).

Slope of the line joining (3,1) and (4,5) is :

Slope of the line joining (5,1) and (6,5) is :

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

Show that the line : through (0, 0) and (2, 3) is parallel to the line through (2, 2) and (4, 5) .

Find the equation of the plane passing through the point A(1, 2, 1) and perpendicular to the line joining the points P(1, 4, 2) and Q(2, 3, 5). Also, find the distance of this plane from the line (x+3)/(2)=(y-5)/(-1)=(z-7)/(-1)

Show that the line joining the origin to the point (2, 1, 1) is perpendicular to the line determined by the points (3, 5, – 1), (4, 3, – 1).

The direction-cosines of the line joining (2, -4, 5) and (0, -6, 4) are

The slope of the line joining points (-4,5) and (0,7) is