Survey
* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project
Rate of Change and Slope Intercept Standard Form and Point Slope Parallel and Perpendicular Lines Scatter Plots Absolute Value Equations $100 $100 $100 $100 $100 $200 $200 $200 $200 $200 $300 $300 $300 $300 $300 $400 $400 $400 $400 $400 $500 $500 $500 $500 $500 Rate of Change and Slope Intercept for $100 Find the rate of change for the following table and explain what it means: Time (Days) Cost ($) 3 75 4 100 5 125 6 150 Answer m = (y2 – y1)/(x2 – x1) m = (100- 75)/(4 – 3) = 25/1 Means the cost is $25 per day Back Rate of Change and Slope Intercept for $200 Write the equation of the line in slope-intercept form that has a slope of -3 and a y-intercept of 5 Answer Slope-intercept Form: y = mx + b So, Y = -3x + 5 Back Rate of Change and Slope Intercept for $300 Write the equation of the line in slope-intercept form: The line through points (-2, 3) and (0, -1) Answer Point: (-2, 3) Point: (0, -1) m = (y2 – y1)/(x2 – x1) m = (-1- 3)/(0 – -2) = -4/2 = -2 Slope-intercept Form: y = mx + b -1 = -2(0) + b -1 = b Thus, y = -2x - 1 Back Rate of Change and Slope Intercept for $400 Write the equation of the line in slope intercept form: Answer Slope Intercept Form: y = mx +b Pick two points on the line: Points: (-4, -1) and (0, -2) m = (y2 – y1)/(x2 – x1) m = (-1- -2)/(-4 – 0) = 1/-4 = -1/4 B = -2 because that is y when x = 0 Thus, the equation of the line is y = -1/4x - 2 Back Rate of Change and Slope Intercept for $500 Write the equation of the line through points (2, 3) and (4, -1) in point-slope form using the point (2,3) AND then convert it to slope intercept form Answer Slope Intercept Form: y = mx +b Points: (2, 3) and (4, -1) m = (y2 – y1)/(x2 – x1) m = (3- -1)/(2 – 4) = 4/-2 = -2 Point-Slope Form: y – y1 = m(x – x1) So, y – 3 = -2(x – 2) y – 3 = -2x + 4 y = -2x + 7 Back Standard Form and Point Slope for $100 Write the formula for the equation of a line in standard form Answer Standard Form: Ax + By = C where A, B, C are real numbers and A and B are not both 0. Back Standard Form and Point Slope for $200 Write the equation of the line in point-slope form: The line through points (2, -3) and (-2, 3) Answer Points: (2, -3) and (-2, 3) m = (y2 – y1)/(x2 – x1) m = (3- -3)/(-2 – 2) = 6/-4 = -3/2 Point-Slope Form: y – y1 = m(x – x1) where (x1, y1) is a point on the line Thus, the equation of the line is y – 3 = -3/2(x - -2) y – 3 = -3/2(x + 2) Back Standard Form and Point Slope for $300 Graph the following linear equation using the intercepts: 2x + 3y = 12 Answer X int: 2x = 12; x = 6 Y int: 3y = 12; y = 4 Back Standard Form and Point Slope for $400 Rewrite the following equation in standard form, using integers: y = -2/5x – (1/5) Answer y = -2/5x – (1/5) 5*y = 5*(-2/5)x – (1/5)*5 5y = -2x – 1 2x + 5y = - 1 Back Standard Form and Point Slope for $500 Write the linear equation from the given graph using point-slope form. Answer Two points on the graph: (0, -3) and (1, -1) m = (y2 – y1)/(x2 – x1) m = (-3 - -1)/ (0-1) m = -2/-1 = 2 y – y1 = m(x – x1) y - -3 = 2(x-0) y + 3 = 2x Back Parallel and Perpendicular Lines for $100 The product of the slopes of two perpendicular lines always equals _____? Answer The product of the slopes of two perpendicular lines always equals -1 Back Parallel and Perpendicular Lines for $200 Which 2 lines are parallel? a) 5y = -3x - 5 b) 5y = -1 – 3x c) 3y – 2x = -1 Answer Writing the lines in slope-intercept form: a) 5y = -3x – 5 y = (-3/5)x – 1 b) 5y = -1 – 3x c) 3y – 2x = -1 3y = 2x – 1 y = (2/3)x – (1/3) a||b y = (-3/5)x – (1/5) Back Parallel and Perpendicular Lines for $300 Write the equation of the line parallel to the given line that passes through the given point: y = (1/3)x + 5 (-3, -3) Answer y = (1/3)x + 5 Parallel lines have the same slope so the slope of the new line will also be (1/3) y = (1/3)x + b Substitute in the point (-3, -3) -3 = (1/3)(-3) + b -3 = -1 + b -2 = b So, y = (1/3)x - 2 Back Parallel and Perpendicular Lines for $400 Write the equation of the line perpendicular to the given line that passes through the given point: y = (½)x - 3 (3, 6) Answer y = (½)x - 3 Perpendicular lines have slopes that are negative reciprocals, so the slope of the new line will be (-2) y = (-2)x + b Substitute in the point (3, 6) 6 = (-2)(3) + b 6 = -6 + b 12 = b So, y = -2x + 12 Back Parallel and Perpendicular Lines for $500 Write the equation of a line perpendicular to the given line that intersects the given line on the yaxis. Write your answer in point-slope form: y = 3x - 8 Answer y = 3x – 8 So, m = 3, a point on the line = (0,-8) Point-Slope Form: y – y1 = m(x – x1) y - -8 = 3(x – 0) y + 8 = 3x Slope of the Perpendicular line: (-1/3) y + 8 = (-1/3)x Back Scatter Plots for $100 Define: Correlation coefficient Answer Correlation coefficient: Tells how closely the equation of a line of best fit models the data in a scatter plot. The correlation coefficient is usually denoted by the letter “r” Back Scatter Plots for $200 Make a scatter plot for the following data comparing practice to score in a violin competition, and draw in the trend line: Practice (weeks) Score 6 8 10 12 14 16 18 15.5 21.5 26.5 34 33 37 41 Answer Back Scatter Plots for $300 What is wrong with the following scatter plot? Answer The line of best fit is not correct. Back Scatter Plots for $400 Use a graphing calculator to find the equation of the line of best fit for the data. Find the value of the correlation coefficient r. Average Speed (mi/h) Time (Hours) 8.5 2.5 7.5 3.75 6.5 4.5 6.0 5.0 5.5 5.5 5.0 6.25 4.0 6.75 3.5 8.75 Answer y = –1.11x + 11.83 r = –0.9760964904 Back Scatter Plots for $500 Use a graphing calculator to find the equation of the line of best fit for the data. Find the value of the correlation coefficient r. GRAPH Year Distance (meters) 0 31.9 1 31.55 2 34.45 3 31.6 4 34 5 36.15 6 35.05 7 38.7 Answer y = 0.864x + 31.15 r = 0.8449426752 Back Absolute Value Equations for $100 Write the equation for the parent function of an absolute value equation: Answer y = |x| Back Absolute Value Equations for $200 Explain how the following graph compares to the graph of the parent function: y = |x| + 4 Answer The graph shifts up 4 units Back Absolute Value Equations for $300 Explain how the following graph compares to the graph of the parent function: y = |x - 2| - 1 Answer The graph shifts down 1 unit and to the right 2 units. Back Absolute Value Equations for $400 Graph: y = |x| - 5 Answer Back Absolute Value Equations for $500 A ___________ is a shift of a graph horizontally, vertically, or both. Answer A translation is a shift of a graph horizontally, vertically, or both. Back