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

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

  3.   A conditional statement consists of a __________ .
    A. conclusion only B. counterexample
    C. hypothesis and a conclusion D. hypothesis 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 = 19, y = 13 B. x = 22, y = 20
    C. x = 12, y = 4 D. x = 15, y = 8
    Hint

  5.   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



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