The equation of the plane through the line of  intersection of the planes ax+by+cz+d=0 and a′x+b′y+c′z+d′=0 and parallel to the line y=0 and z=0 is

The equation of a plane through the line of intersection of the planes ax + by + cz + d - 0 and a′x+b′y+c′z+d′=0 is (ax+by+cz+d)+λa′x+b′y+c′z+d′=0or  xa+λa′+yb+λb′+zc+λc′+d+λd′=0 This is parallel to the x-axis, i.e., y=0,z=0. Therefore, 1a+λa′+0b+λb′+0c+λc′=0 or  λ=−aa′ Putting the value of λ in (i), the required plane is ya′b−ab′+za′c−ac′+a′d−ad′=0 or  ab′−a′by+ac′−a′cz+ad′−a′d=0