1. The problem statement, all variables and given/known data Find the parametric equation for a line of intersection of these two planes x+2y+3z=0 4x+5y+6z=5 2. Relevant equations Normal to plane 1= <1,2,3> Normal to plane 2= <4,5,6> 3. The attempt at a solution I know the way to do this problem is to take cross product of two normals etc etc, but i want to know if the way i did this is correct also. I already turned the work in so theres nothing i can do to change it but the curiosity is killing me. First, i set the two planes equal to each other 4x+5y+6z-5=0 x+2y+3z=0 => x+2y+3z=4x+5y+6z-5 (please correct me my thinking process is wrong,im winging it) => 3x+3y+3z=5 => x+y+z=5/3 (now im thinking this is the equation of the intersection of the two planes but this isnt the equation of a line, it looks like a plane, or is it?) so i took a point on this set, (5/3,0,0) and two other points (0,5/3,0) and (0,0,5/3) i did <0,0,5/3> - <0,5/3,0> = <0,-5/3,5/3> as a directional vector. so L(t)= (5/3,0,0) + <0,-5/3,5/3>t x=5/3 y=-5/3t z=5/3t IS any of this wrong?!