Consider the planes 2x + 1y + 5z = 1 and 2x + 5z = 0.

(a) find the unique point p on the y-axis which is on both planes. ( ? , ? , ? )

(b) find a unit vector u with positive first coordinate that is parallel to both planes.
? i + ? j + ? k

(c) use the vectors found in parts (a) and (b) to find a vector equation for the line of intersection of the two planes, r(t) =
? i + ? j + ? k