1. The problem statement, all variables and given/known data The acute angle between two planes is called the dihedral angle. Plane x−3y+2z=0 and plane 3x−2y−z+3=0 intersect in a line and form a dihedral angle θ . Find a third plane (in point-normal, i.e. component, form) through the point (-6/7,0,3/7) that has dihedral angle θ/2 with each of the original planes. Do the three planes intersect at a point or in a line? Explain all steps carefully. 2. Relevant equations cosθ=|n1 (dot product) n2| /|n1||n2|, 3. The attempt at a solution I found the dihedral angle of the first two planes to be 1/2, but then I'm not sure what to do after that.