[" 7.Show that the equation of the straight line joining the points "],[([a,b)," and "(c,d)," can "," be "," written "," as "],[(x-a)(y-d),=(x-c)(y-b)]]

What is the equation on the straight line joining the origin to the point of intersection of the lines x/a+y/b=1 and x/b+y/a=1 ?

If (x, y) is any point on the line joining the points A(a, 0) and B (0, b), then show that (x)/(a)+(y)/(b) = 1

The equation of the straight line through the origin and parallel to the line (b+c)x+(c+a)y+(a+b)z=k=(b-c)x+(c-a)y+(a-b)z are

The equation of the straight line through the origin and parallel to the line (b+c)x+(c+a)y+(a+b)z=k=(b-c)x+(c-a)y+(a-b)z are

The equation of the straight line through the origin and parallel to the line (b+c)x+(c+a)y+(a+b)z=k=(b-c)x+(c-a)y+(a-b)z are

The equation of the straight line through the origin and parallel to the line (b+c)x+(c+a)y+(a+b)z=k=(b-c)x+(c-a)y+(a-b)z are

The equation of a line which bisects the line joining two points (2,-19) and (6,1) and perpendicular to the line joining two points (-1, 3), and (5,-1), is ................ A) 3x-2y=30 B) 2x-y-3=0 C) 2x+3y=20 D) None of these