8.13 Real Number System and Properties Complete the "Think About a Plan" ­ Order of Operations and Evaluating Expressions Worksheet. Homework Answers: pages 7 ­ 8 pages 13 ­ 14 9. p + 4 27. 8 ­ 9r 11. n/8 29. (3/7)y ­ 4 13. t/82 32. 13b 15. 5n + 6.7 17. 5 more than a number q 19. the product of 12 and x 21. one more than the product of 9 and a number n 23. the difference of 15 and the quotient 36. a) 24.0 cubic inches b) 2.0 cubic inches 37. 256 39. 5 41. 12 45. 27 47. 6 49. 68 51. 3 of 1.5 and d 25. 5 more than the product of 9 and a number nÍž 9n + 5 1 8.13 Real Number System and Properties 2 8.13 Real Number System and Properties 3 8.13 Real Number System and Properties 1.3 The Real Number System If the pattern continues, which will be the first figure to contain more than 200 square units? Explain your reasoning. 2 1 3 4 A. Understanding Square Roots A number "a" is a square root of a number if Example: If You can simplify certain square roots and determine the exact answers. 1. 2. 3. 4. 4 8.13 Real Number System and Properties B. Subsets of the Real Number System *rational number: * integer: *whole number: *natural number: * irrational number: 5 8.13 Real Number System and Properties 6 8.13 Real Number System and Properties Apply it: To which subsets of real numbers does each number belong? a. 15 d. b. -1.4583 e. c. f. -4 Look at the lesson check on page 20 in your book. 1.4 Properties of Real Numbers 1. Commutative Properties of Addition and Multiplication ­ Changing the order of the addends does not change the sum. ­ Changing the order of the factors does not change the product. 2. Associative Properties of Additon and Multiplication. ­Changing the grouping of the addends does not change the sum. ­Changing the grouping of the factors does not change the product. 3. Identity Properties of Addition and Multiplication ­The sum of any real number and 0 is the original number. ­The product of any real number and 1 is the original number. 7 8.13 Real Number System and Properties 4. Zero Property of Multiplication ­­The product of "a" and 0 is zero. 5. Multiplication Property of -1 ­­The product of ­1 and "a" is negative 1. What property is illustrated by each statement? a. 42 * 0= 0 b. (y +2.5) +28 = y + (2.5 +28) c. (y + 2.5) + 28 = 28 + (y + 2.5) d. 10x + 0 = 10x Explain the properties used in the following scenario: A movie ticket costs $7.75. A drink costs $2.40. Popcorn costs $1.25. what is the total cost of a ticket, a drink, and popcorn? Use mental math. (7.75 +2.40) + 1.40 = (2.40 + 7.75) + 1.25 = 2.40 + (7.75 + 1.25) = 2.40 + 9 = 11.40 ** Look at lesson check on pg. 26 8 8.13 Real Number System and Properties 1.7 - The Distributive Property 6. The Distributive Property a(b+c) = ab +ac (20 +6)4 = 20(4) + (6)4 1. ­3(x +8) 2. (5b ­ 4)(­7) 3. 12(3 ­ ) 4. 5(x + y ­ z) + 4(2x ­ 3y + 6z) 5. 2(­3x + 5y ­ 4z) ­ 6( x ­ y + 2z) 9 8.13 Real Number System and Properties 6. 7. Homework: pg 20 #9-36 (odd), 52-55, 57-63 pg. 26 # 7-19 (all), 36-46 (all) 10 8.13 Real Number System and Properties 11