Show that the two lines `(x-5)/4=(y-7)/4=(z+3)/-5` and `(x-8)/7=(y-4)/1=(z-5)/3` intersect each other . Find also the point of intersection.

Show that the two lines (x-1)/2=(y-2)/3=(z-3)/4 and (x-4)/5=(y-1)/2=z intersect each other . Find also the point of intersection.

Show that the lines : (x+1)/3=(y+3)/5=(z+5)/7 and (x-2)/1=(y-4)/3=(z-6)/5 intersect each other. Also find their point of intersection.

Show that the two lines x+1/3=y+3/5=z+5/7 and x-2/1=y-4/3=z-6/5 intersect each other. Find also the point of intersection.

Show that the lines: (x-1)/3=(y+1)/2=(z-1)/5 and (x-2)/4=(y-1)/3=(z+1)/-2 do not intersect.

Show that the lines (x-1)/23=(y+1)/2=(z-1)/5 and (x-2)/4=(y-1)/3=(z+1)/-2 do not intersect.

The lines x+3y-1=0 and x-4y=0 intersect each other. Find their point of intersection.

Show that the following lines are coplanar (5-x)/-4=(y-7)/-4=(z+3)/-5 and (x-8)/7=(2y-8)/2=(z-5)/3

Show that the lines : (x-3)/2=(y+1)/-3=(z-2)/4 and (x+2)/2=(y-4)/4=(z+5)/2 are perpendicular to each other.

Show that the lines (x+1)/-3=(y-3)/2=(z+2)/1 and x/1=(y-7)/-3=(z+7)/2 intersect. Find the point of intersection and the equaion of the plane contianing them.