Sections 2.5 - Applications of Linear Equations

Section Objectives

  1. Construct a scatterplot.
  2. Recognize a linear relationship, and determine an equation that describes the relationship.
  3. Use an equation to make predictions in a linear relationship.
  4. Compute an average rate of change.



Scatterplots and Linear Trends

A scatterplot is a collection of plotted points obtained from ordered pairs. In a scatterplot, the plotted points are not connected with a curve.



We often use scatterplots to identify patterns and recognize trends. If plotted points appear to approximately "fit" a line, we can use a linear equation to describe the pattern and predict behavior. Finding a "best fit" line is a very important practical problem.



There are well-defined procedures for finding best fit lines. For the most part, we will use graphs to estimate best fit lines.



Example