A. Name the property illustrated by each of the following.
1. 4 + 9 = 9 + 4 6. (5 + 7) + 9 = 5 + (7 + 9)
2. 101 + (-101) = 0 7. 3 – 12 = – 8
3. 1 ∙ 13 = 13 8. 0 + (- 9) = – 9
4. 57(-63) = (-63) (57) 9. (-1) (-1) = 1
5. -9(5 + 7) = -45 +(- 63) 10. 7 ∙ (21 + 4) = (7 ∙ 21) + (7 ∙ 4)
B. Fill in the blanks to make the following statements true.
1. 8 + ____ = 9 + 8 6. 13 + (____) = 0
2. 12 + ____ = 12 7. 9 + (____ + 4) = (____ + 11) + 4
3. 5(3 + 8) = ____ + 40 8. – 28(____ + 5) = – 84 + (- 140)
4. – 7+(____) = 0 9. 11(6 ∙ ____) = (11 ∙ 6) ∙ 8
5. ____ + 32 = 0 10. (−5) + (__) = 0
C. Complete the statements below and identify the property used.
1. 6(4 + 7) = 6 ∙ _____ + _____ ∙ _____
2. (3 + 8) ∙ 3 = 3 ∙ _____ + _____ ∙ _____
3. (6 + 8) + 9 = _____ + ( _____ + _____ )
4. 7 ∙ [( - 2) ∙ 5] = [ _____ ∙ _____ ] ∙ _____
5. 6 ( 4 – 9) = _____ ∙ _____ – _____ ∙ _____
6. 9 ( _____ + 12) = 9 ∙ 4 + _____ ∙ 12
7. 12 + (7 + 10) = ( _____ + _____ ) + _____
8. _____ ∙ 15 = _____ ∙ 9
9. 8 ∙ _____ = 1
10.0 = 11 + _____