If a is even and b is even, then their product ab is
Which expression has an odd integer value for all integers x and y?
A) x + 2y
B) 3x + 2y
C) 3xy + 5y
D) x^2 + 2y
E) 2xy^2 + 1
1. The correct answer is even. Two even numbers multiplied together will always yield an even number.
2. Two times any number is even and any even number plus 1 is odd. The correct answer is 2xy^2 + 1.