3. Let P, be the plane through the origin containing the vectors [1, 2, -1] and [0, 1, 1]. Let P2 be the plane through the point (1, 1, 1) parallel to the vectors (-1, 2, 2] and [3,4,-2].

(a) Find an equation for Pin normal form ax + by + cz = 0.

(b) The planes P, and P2 intersect in a line. Find a parametric equation for this line.