# slope intercept form2

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- 1. Jeudi 23 Septembre Warm up A tennis club membership costs $5 a year. In addition to this flat fee, you must pay $2 every time you reserve a court. Which function rule describes the cost (y) for the number of times you reserve a court(x) A. y = 7 B. y = 5x + 2 C. y = 7x D. y = 2x + 5

2. x y 0 1 2 3 y = 2x + 5 3. Slope intercept form of linear functions We have learned that every linear function can be expressed by a function rule that looks like this : y = ___ x + ___ 4. In algebra, we call this form of function rule aslope intercept form. You'll find it usually expressed asy= mx + b y and x are variables. They vary! m and b are numbers, constant. They stay the same! 5. 40% of the 8th grade math EOG questions, are about finding the value of m or b using: The graph The function rule Coordinates of 2 points a real life situation So let's say it's a... VERY important lesson! 6. ba.k.a the y-intercept For the real life situation, b is always the flat fee,the guaranteed salary... Basically the part of the cost (salary) that does not depend on the other variable On the graph, you can always read it where the line intersects the y-axis. Therefore it's called the y intercept! 7. y = mx + ..... y = mx + ...... Guided practice 8. 9. Independent practice Find the y-intercept ofeach linear function 10. 11. Vendredi 24 Septembre Warm up What is the y-intercept of the following lines? 12. What is the slope of a line? Slope : The number that determines the steepness of a line 13. Where do we see natural slopes??? 14. 15. 16. Watch the 2nd video and try to take notes of the 4 different types of slope. 17. Slopes can be: positive negative zero undefined *Look at the line from left to right (like reading) 18. 19. 20. cross country skiing 21. 22. Is the slope positive, negative, undefined or none at all??? 23. Is the slope positive, negative, undefined or none at all??? 24. Is the slope positive, negative, undefined or none at all??? 25. Is the slope positive, negative, undefined or none at all??? 26. Is the slope positive, negative, undefined or none at all??? 27. Is the slope positive, negative, undefined or none at all??? 28. Is the slope positive, negative, undefined or none at all??? 29. Is the slope positive, negative, undefined or none at all??? 30. Is the slope positive, negative, undefined or none at all??? 31. Review game 32. 33. 34. 35. 36. 37. 38. 39. 40. 41. 42. 43. Lundi 27 Septembre Warm up 1) What is the y-intercept of this line? 2) Is the slope of this line positive, negative zero or undefined? 44. Quick review: What do we know so far on linear functions ? 45. Objective 1: Finding slope on the graph Watch the following segment of video (what is slope from 2:00 mark) and write down steps to find the slope of a line on the graph. 46. Finding slope on the graph step by step Step 1:Determine sign of theslope (+,-,...) Step 2:Pick 2 points on theline (corners of unit squares) Step 3:Draw a slope triangleRise first, run second.Rise : up +, down -Run : right +, left - Step 4:Write the fractionrise/run, simplify, check thesign 47. Guided practice S tep 1: Step 2: Step 3: Step 4: 48. S tep 1: Step 2: Step 3: Step 4: 49. S tep 1: Step 2: Step 3: Step 4: 50. Independent practice: (will be evaluated) Front: The 2 points are already picked for you (step 2), focus on the 3 other steps. Back page:You have to pick the 2 points, remember to pick them on corners of unit squares Chek with your partners, ask for help, do not stay passive. 90% of the learning happens here! 51. 52. 53. Mardi 28 Septembre Warm up 54. Homework check 55. 56. 57. Objective 2: Matching a linear equation with a graph Which linear equation describes the blue line? A . y = 3x + 2 B. y = -3x - 2 C. y = 3x - 2 D. y = 4x - 2 Step 1 : Find the y-intercept of the blue line. Eliminate answers based on the "b". St ep 2:Determine sign of slope. Eliminate answers based on the sign of "m" St ep 3:Find slope. You should have only one possible answer 58. Independent practice 59. 60. Y = mx + b 61. Objective 2:Which linear equation describes the blue line? A.y = (2/3)x + 2 B. y = ( -3/2)x + 2 C. y = (3/2)x- 3 D. y = (-2/3)x + 2 62. Which graph corresponds to y = (1/2)x - 1 ? 63. Pop quiz 3 64. 65. End of class game 66. 67. 68. Mercredi 29 Septembre Warm up y = 2x + 1? 69. Pop quiz 3 for the same 4 graphs, write the function rule 70. Homework check 71. Objective 3:Find the slope of a line knowing the coordinates of 2 points What is the slope of aline going through (1,2) and (3,6) ? 72. Could we do this without graphing? 73. Objective 3: Find the slope using coordinates of 2 points 74. Step by step guided practice Step 1:Mark (x 1 ,y 1)and (x 2 ,y 2)under the points. St ep 2:Write down the formula St ep 3:Plug in the numbers in your formula. Simplify 75. Find the slope of the line that goes through the two points given. 76. 1. 2. TRY: Find the slope of the line that goes through the two points given. 77. 78. Jeudi 30 Septembre Warm up Find the slope of the line going through the following points 79. Homework check 80. Quiz 3 : study guide Obj 2: Match y=mx+b with graph 81. Objective 1 example problem S1: S2: S3: S4: 82. Objective 2: example problem Wh ich function rule best describes the blue line? A. y = 1x + 2 B. y = -2x + 1 C. y = 0.5x +1 D. y = 0.5x - 1 S1: S2: S3: 83. Objective 3 example problem Fi nd the slope of the line going through (-1,3) and ( 5, 1) S1: S2 S3: 84. Review game Everyone in the group does the work! Rewards will go to the winners + the groups where I see REAL group work 85. 86. 87. 88. 89. 90. Which line is best described by : y = -2x -1? 91. Which line best describes the function ruley = 1/2x + 1 92. 93. Which function rule best describes the blue line? A. y = 4x - 1 B. y = 4x - 1 C. y = (-1/4)x + 1 D. y = (-1/4)x - 1 94. 95. 96. Vendredi 1er Octobre Warm up Wr ite the function rules that can describe the blue lines: 97. Quiz # 3 Ob jective 1:Find the slope of the following lines using the graph 98. 99. Write the function rules that best describe the following lines: 6) 7) Obj. 2: Match a function rule with a graph 100. 8) Which function rule best describes the line? A. y = (1/2)x + 4 B. y = 4x + 2 C. y = -2x + 4 D. y = 2x + 4 101. 9) Which function rule best describes the line? A. y = -1x - 2 B. y = -3x - 2 C. y = 1x + 2 D. y = 1x - 2 102. 10) Which graph represents the function y = (-1/2)x + 3 ? 103. Find the slope of the lines going through: 11)(2,4) and (3,8) 12) (-1, 3) and (4, -7) 13) (-2,5) and (1,5) 14) (2,4) and (2,10) Obj. 3: 104. 15) Round 46 to the nearest tenth 16) Is 5 rational or irrational? 17) Is 49 rational or irrational? 18) Put 96 between 2 consecutive integers < 96 < 1 9) Is this a function? x y 105. 20. 106.