By using standard formulae, expand the following: (3x 2 y + 5z) 2

(3x 2 y + 5z) 2 = (3x 2 y) 2 + 2 (3x 2 y)(5z) + (5z) 2 = 9x 4 y 2 + 30x 2 yz + 25z 2