Math Problem Statement

Determine the equations of the trend lines for the two scatter plots shown in the graphs.

Solution

Let’s analyze the graphs and calculate the equations of the trend lines shown in the two scatter plots.

Graph 5

The line is linear, and we can find its equation using the slope-intercept form y=mx+by = mx + b, where mm is the slope and bb is the y-intercept.

  1. Identifying points: Two points on the line are approximately (0,8)(0, 8) and (40,0)(40, 0).
  2. Slope: m=y2y1x2x1=08400=840=0.2m = \frac{y_2 - y_1}{x_2 - x_1} = \frac{0 - 8}{40 - 0} = -\frac{8}{40} = -0.2
  3. Intercept: b=8b = 8 (where the line crosses the y-axis).
  4. Equation: y=0.2x+8y = -0.2x + 8

Graph 6

Similarly, we determine the slope and intercept for this graph.

  1. Identifying points: Two points on the line are approximately (0,80)(0, 80) and (10,0)(10, 0).
  2. Slope: m=y2y1x2x1=080100=8010=8m = \frac{y_2 - y_1}{x_2 - x_1} = \frac{0 - 80}{10 - 0} = -\frac{80}{10} = -8
  3. Intercept: b=80b = 80 (where the line crosses the y-axis).
  4. Equation: y=8x+80y = -8x + 80

Final Equations:

  1. Graph 5: y=0.2x+8y = -0.2x + 8
  2. Graph 6: y=8x+80y = -8x + 80

Do you have any questions or want me to clarify any part?


Related Questions:

  1. What are the steps to calculate the equation of a trend line if only data points are given?
  2. How can you estimate the correlation between the variables in each graph?
  3. What does the negative slope in each trend line indicate?
  4. How would the equations change if the axes were reversed?
  5. Can you explain the practical interpretation of these trend lines in real-world scenarios?

Tip:

Always start with identifying two clear points on the line to ensure accuracy when calculating the slope and intercept!

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Linear Equations
Slope-Intercept Form
Graphing

Formulas

y = mx + b
m = (y2 - y1) / (x2 - x1)

Theorems

Slope-Intercept Form

Suitable Grade Level

Grades 8-10