If n is a natural number, then (7(n2) + 7n) is always divisible by:
Choose one
A) 3 and 7	B) 14 only	C) 7 only	D) 7 and 14	E) NONE
Solution   (7n2 + 7n) = 7n(n + 1), which is always divisible by 7 and 14 both, since n(n + 1) is always even.   Answer 7 and 14
<result>D</result>
If n is a natural number, then (7(n2) + 7n) is always divisible by: