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 = 21, y = 3 B. x = 7, y = 12
    C. x = 10, y = 9 D. x = 12, y = 6
    Hint

  2.   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 = 19, y = 13 B. x = 15, y = 8
    C. x = 12, y = 4 D. x = 22, y = 20
    Hint

  3.   Identify the hypothesis in the following statement: If x – 3 = 9, then x = 12.
    A. x – 3 B. x = 12
    C. x D. x – 3 = 9
    Hint

  4.   Identify the conclusion in the following statement: If 13b + 12 = 77, then b = 5.
    A. b = 5 B. 13b + 12
    C. b D. 13b + 12 = 17
    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 = -1, y = 1
    C. x = 0, y = 1 D. x = 0, y = 0
    Hint



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