1.   Which values are a counterexample to the given statement?
If x + y = an even number, then x is even and y is even.
    A. x = 10, y = 9 B. x = 7, y = 12
    C. x = 12, y = 6 D. x = 21, y = 3
    Hint

  2.   Identify the conclusion in the following algebraic statement:
If a = 3, then 2a + 1 = 7.
    A. 2a + 1 = 7 B. a = 3
    C. 2a D. 2a + 1
    Hint

  3.   A conditional statement consists of a __________ .
    A. counterexample B. hypothesis and a conclusion
    C. hypothesis only D. conclusion only
    Hint

  4.   Which values of x and y are counterexamples to the given statement?
If xy = an even number, then both x and y are even numbers.
    A. x = 15, y = 8 B. x = 19, y = 13
    C. x = 12, y = 4 D. x = 22, y = 20
    Hint

  5.   Which values are a counterexample to the given statement?
If x × y = 0, then x must be 0.
    A. x = 5, y = 0 B. x = 0, y = 1
    C. x = 0, y = 0 D. x = -1, y = 1
    Hint



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