Page 134 - IM_Algebra1_FL Print Sample.pdf

Lesson 5: Fitting Lines
• Choose the best linear model for data from among choices.
• Interpret the slope and vertical intercept of the equation of the line of best t. • Use technology to nd the line of best t.
Lesson Narrative
The mathematical purpose of this activity is for student to informally assess the t of various lines to data, to use technology to nd the line of best t, and to interpret the slope and vertical intercept of the linear model. The work connects to previous work because students created scatter plots and created linear models for the data. The work connects to upcoming work because students will use the correlation coe cient to describe the strength of the linear relationship. When students sort scatter plots into linear and nonlinear categories, and when they organize lines of best t by the goodness of t, they are engaging in MP7 because they are analyzing representations and structures closely, and making connections. Students are reasoning abstractly and quantitatively (MP2) when they interpret the meaning of the slope and vertical intercept in context.
Required Materials
Pre-printed slips, cut from copies of the blackline master
Required Preparation
Print and cut up slips for the card sort. One copy of the blackline master for every group of 2 students. To nd best t lines, students will need access to technology that will compute the least-squares regression lines for a set of data.
Acquire devices that can run Desmos (recommended) or other graphing technology. It is ideal if each student has their own device. (Desmos is available under Math Tools.)
Student Learning Goals
• Let’s nd the best linear model for some data. 5.1 Pitching Lines
Warm Up: 5 minutes
The mathematical purpose of this activity is for students to be able to visually assess the best line that ts data among a set of choices. Monitor for students using the terms slope and -intercept.
Launch
Provide students access to the images. Give students 2 minutes of quiet time to work the questions.
Unit 3 Lesson 5: Fitting Lines 67