1 091 Exam 1 Review (Sections 1.3 – 2.5, 2.7, Handouts A, B, C) KNOW THE DEFINITIONS OF ALL KEY TERMS PRESENTED IN CLASS. ALSO KNOW WHAT ALL SYMBOLS MEAN (EX. , , , , ETC.) Adding/Subtracting Fractions Reduce answers to lowest terms. 1. 2. 1 1 1 8 2 2 3 3 Multiplying/Dividing Fractions Reduce answers to lowest terms. 3. 2 5 3 8 4. 2 4 3 3 5. 4 5 Comparing Fractions 6. True or False 11 1 36 4 ________________ Review Definitions Absolute Value – distance between a number and 0 on the number line Equation – solving for a variable: has an = sign (ex. 2x - 4 = 8) Expression- just simplify: no = sign (ex. 2x - 4) Term – in expression, parts that are added (ex. in 2x – 4, 2x and -4 are terms) Like Terms – have the same variables to the same power (ex. 3x 2 y and 5 x 2 y are like terms) Factor – the numbers or variables that are multiplied (ex. in 2x-4, 2 and x are factors) Expressions For the expression: x 4 6 List the: 7. Numerical coefficient________ 8. Variable____________ 9. Constant____________ 10. 2 terms______________ 11. 2 factors_____________ 2 Match the equation with the corresponding property. (You can use them more than once.) 12. 3 3 9 4 3 12 _______________________________________ 13. 6∙4∙2 = 6∙2∙4 _______________________________________ 14. 4 + (3 + 2) = (4 + 3) + 2 _______________________________________ 15. 24 16. 8 0 8 17. (2 +7) + 12 = (7 + 2) + 12 _________________________________________ 18. (3 + 2x) ∙2 = 6 + 4x 19. 20. (2 + 7) + 12 = 12 + (2 + 7) __________________________________________ 21. 4∙(3∙7) = (4∙3)∙7 1 1 24 12 12 0 5 5 ________________________________________ _________________________________________ _________________________________________ __________________________________________ __________________________________________ Commutative Property of Addition, Commutative Property of Multiplication, Associative Property of Addition, Associative Property of Multiplication, Identity Property of Addition, Identity Property of Multiplication, Inverse Property of Addition, Inverse Property of Multiplication, Distributive Property Remember: Commutative Property (both addition and multiplication) – can change order Associative Property (both addition and multiplication) – can change grouping Identity Property for Addition – adding 0 doesn’t change the answer 7 Identity Property for Mult. – multiplying by 1 (in any form, ex. ) doesn’t change the answer 7 Inverse Property for Addition – a number added to its opposite equals 0 Inverse Property for Multiplication – a number multiplied by its reciprocal equals 1 Distributive Property – involves both multiplication and addition/subtraction True or False: 22. 6.92 is a natural number 23. 7 is an irrational number 24. 0 is a whole number 25. is a real number 26. 82 64 27. 4 4 ________________ ________________ ________________ ________________ ________________ ________________ 3 Subsets, Union, and Intersection Let: A = {1,2,3,4,5} B = {1,2,3,5,8,10,11} Place , ,, or to fill in the blank. 28. A____B 29. 2____C 32. A____C 33. {6}____A C = {1,2,3,4,5,6,7,8} 30. ____A 34. 6____B 31. D = {9, 12} A____A Using sets A, B, and C from above, complete: 35. A B_______________________ 36. C _________ 37. B D __________ 38. B C_______________________ 39. A C___________ 40. A C __________ 41. A { } ____________ Remember: 0 0 any # any # undefined 0 Signs: +∙+ = + −∙−=+ + ∙ − = − and − ∙ + = − Perform the indicated operations and reduce all answers to lowest terms: 42. 2 5 4 1 6 3 2 43. 3 6 + [ (4−5) − (2−8)] 20 18 9 2 3 2 44. 10 2 3 5 2 4 45. 3(5 2 ) (3 2 7)(5) 32 5 2 (1) 46. 2(5) (3)(2) 2 6 10 2 1 2 2 Simplify: 47. 3 2 4( x y) 4 2(2 y 2 x) 48. y 2 2 x 2 (3x 2 y 2 ) 4 x 2 2( x y) Solve: (Remember to check your answers!) 49. 5 x 20 6 50. 3(2 x 4) 7 2( x 6) 1 51. 7( x 4) 2 x 5 x ( x 28) 52. 2 3 5 1 x x 3 4 12 2 53. 6x 2 x 4 4 x 6 54. 2 3(2 3x) 3(3 x 2) 2 55. 1 2 x 2 3 x 5 4 3 5 6 Evaluate when x 1 2 and y 2 3 56. x2 5 x 2 y 57. 8x2 2 x 3 y Ratios and Proportions Ratio: quotient of 2 quantities, written: a to b, a:b or a (Note: a & b must be in the same units) b Solve: 58. Write the ratio of 10 minutes to 1 hour. Proportion: a statement of equality between two ratios a c a and c must have the same units b d b and d must have the same units To solve a proportion, cross multiply: a∙d = b∙c Solve: 59. Amy Smith earns $380 in 2 weeks. How much will she earn in 52 weeks? Answers to Math 091 Exam 1 Review 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 13 5 1 8 8 7 1 2 3 3 5 12 1 2 32 35 False 1 6 x 4 x , 4 6 1 ,x 6 Identity – Multiplication Commutative - Multiplication Associative - Addition Inverse - Multiplication Identity - Addition Commutative - Addition Distributive Inverse- Addition Commutative - Addition Associative – Multiplication False True True True False True 34. 35. 36. 37. 38. 39. 40. 41. 42. 43. 44. 45. 46. 47. 48. 49. 50. 51. 52. 53. 54. 55. 56. 57. 58. 59. {1,2,3,4,5,8,10,11} C {1,2,3,5,8} A C 1 4 4 8 2 undefined 8 x 16 y 2 2 x 2 y 2 5x 2 y x= 24 x2 x=0 x 1 no solution all real numbers x 2 3 14 3 1 6 $ 9880 7