State a normal of a line that is ; parallel to 2x-4y+5=0.
state ANY normal line? normal to what?
well, ok. solve this line for y. then just change the constant term to whatever you want, and viola!
EDIT: i just noticed your title. what plane are you referring to? 2x - 4y + 5 = 0 is a plane? not a line in the Cartesian coordinates?