1.	Factor x2 – 16.
		A.	(x + 4)(x – 4)	B.	(x – 4)(x – 4)
		C.	(x + 2)(x – 8)	D.	(x + 4)(x + 4)
		Hint
	2.	Factor 4y2 – 9.
		A.	(2y + 3)(2y + 3)	B.	(2y – 3)(2y – 3)
		C.	(2y + 3)(2y – 3)	D.	prime
		Hint
	3.	Factor r4 – 81.
		A.	(r2 + 9)(r + 3)(r - 3)	B.	prime
		C.	(r2 + 9)(r2 + 9)	D.	(r + 3)2(r + 3)2
		Hint
	4.	Factor 7xy2 - 28x3
		A.	7x2y2(1 + x)	B.	prime
		C.	7x(y + 2x)(y - 2x)	D.	(7xy + x)(y – 28x2)
		Hint
	5.	Factor 16b4 – 36b2.
		A.	2b2(4b – 3)(4b + 3)	B.	4b2(2b – 3)(2b + 3)
		C.	2b2(2b – 3)(2b + 3)	D.	4b2(4b – 3)(4b + 3)
		Hint