Which of the following pair of linear equations represent the two parallel tracks of the railway line?
a) x-2y-4=0 and 2x + 4y - 12 = 0
c) 2x + 4y -12 = 0 and x +2y-4=0
b) x +2y-4=0 and 2x + 4y +12 = 0
d) 2x + 4y + 12 = 0 and x-2y-4=0
a) x-2y-4=0 and 2x + 4y - 12 = 0
c) 2x + 4y -12 = 0 and x +2y-4=0
b) x +2y-4=0 and 2x + 4y +12 = 0
d) 2x + 4y + 12 = 0 and x-2y-4=0