If (x + 1) times (4x + 1) is an odd integer, then x must be:	Choose the correct choice from the following answers
A) an odd integer
B) an even integer
C) a prime number
D) a composite number
E) a negative integer
Solution:   (x + 1) times (4x + 1) means (x + 1)(4x + 1)   (x + 1)(4x + 1) = 4x^2+5x+1   For 4x^2+5x+1 to be odd, 5x+1 must be odd since 4x^2 is always even.   So 5x must be even, hence x must be even.   Therefore x is an even integer.   Answer: an even integer
<result>B</result>
If (x + 1) times (4x + 1) is an odd integer, then x must be: