Connecting Algebra to Geometry

Jeanne Cavuto

Connecting Algebra to Geometry

The Beach Trend – 6 Year Survey: Points and Lines in a Plane

Concepts: Materials

·  Creating Lists of two-variable data TI 83/84 Plus

·  Scattered Plots Cabri geometry II Software

·  Line of Best Fit

·  Points on a Plane

·  Linear Equations in Slope-Intercept Form

·  Linear Equalities

·  Parallel Lines in the Plane

·  Mathematical reasoning

Overview

This investigation activity gives participants a new way to view linear equations in the plane related to survey data from the student’s summer experiences. The outcome of this activity is a combined view of linear equations and linear graphs as a part of a continuum including linear equalities and inequalities.

Step 1: Survey the class to record the number of students that went to the beach during the summers of 2000 -2006, respectively. Enter data (ordered pairs) into calculators – L1: x-coordinate (years – numbered 0 through 7, 2000 being 0); L2: y-coordinate (number of students at the beach) PRESS: STAT, EDIT, ENTER – record numbers in respective columns, be sure to press enter after each insert

Step 2: Press WINDOW, set values to accommodate data

Step 3: Press 2nd, Y=, STAT PLOT, ENTER turn plot on – highlight all designated commands, ENTER

Step 4: Press Graph

(this is an example, your graph will represent your data)

Step 5: Display line of Best Fit – Press STAT, CALC, LIN REG, ENTER, Y=, VARS, STATISTICS, EQ, ENTER, GRAPH

Step 6: Pick two points on the line and use these same points to construct an equivalent line in Cabri, Jr. – CLEAR, APPS, 5: CABRI, JR., PRESS ANY KEY

Step 7: Slope of Line – use TI 84 Plus Activity “Points and Lines in the Plane” (attachment)

to achieve remaining concepts in lesson

This lesson can be an enrichment review for the Advanced Classes or be modified as a teaching tool for the Basic and Below Level Classes. Reference to this lesson may continue throughout the first marking period.

Advanced Class: graphing trend lines, predictions, slope, y-intercept, linear

equations and inequalities

Basic Classes: review of scattered plots, trend lines, slope, y-intercept,

equations of lines, inequalities

Below Level Classes: ordered pairs, graphing on the coordinate plane, slope,

y-intercept, equations and inequalities,