Linear Models

In this video lesson, students use linear functions to model real-world situations (MP4). Students are given data for an almost linear relationship and develop a linear model. They use their model to make predictions and discuss the reasonableness of the model. Sometimes it is difficult to tell from the information given if a linear model is appropriate. When none of the given data are perfectly fit by a linear function, students have to determine whether a linear approximation is reasonable and for which values it would be reasonable. Students also use piecewise linear graphs to find information about the real-life situation they represent. In situations where a quantity changes at different constant rates over different time intervals, students model the situation with a piecewise linear function (MP4).

Grade 8, Episode 11: Unit 5, Lessons 9 & 10 | Illustrative Math