Show that the lines are `3x+2y+9=0 and 12x+8y-15=0` are parallel lines.

Show that the lines 2x+3y+19=0 and 9x+6y-17=0 , cut the coordinate axes at concyclic points.

Show that the straight line x-2y+3=0 and 6x+3y+8=0 are perpendicular .

Show that the lines 4x+y-9=0,x-2y+3=0,5x-y-6=0 make equal intercepts on any line of slope 2.

Find the equation of the line through the intersection of lines 3x+2y-5=0and 4x-y-3=0and is parallel to 3x+y+2=0

Find the equation of the line through the intersection of lines 3x+2y-5=0and 4x-y-3=0and is parallel to 3x+y+2=0 is perpendicular to the line 7x+3y-4=0

Find the equation of the straight line passing through the intersection of the lines x-2y=1 and x+3y=2 and parallel to 3x+4y=0.

Show that the line x^(2)-4xy+y^(2)=0 and x+y=3 from an equilateral triangle.

The lines x+2y-3=0 and 3x-y+7=0 are:

Show that the equations 3x+y+9z=0, 3x+2y+12z=0 and 2x+y+7z=0 have non-trival solutions also.