Below are two sketches that I did when I first learned Geogebra. I adapted them from manual. I hope you enjoy using them in your classes. You can use this accompanying document for students to work on in class Integer Operations.pdf

Integer Addition

One of the most common mistakes in mathematics is a students ability to simplify numerical expressions involving positive and negative numbers. Below you will find a sketch that students can manipulate to help answer some of the following questions:
  1. When adding numbers with different signs, how do you know what the sign of the sum will be?
  2. How are adding two positive numbers similar to adding to negative numbers? How are they different?

Integer Addition

This is a Java Applet created using GeoGebra from www.geogebra.org - it looks like you don't have Java installed, please go to www.java.com

Move the red a blue sliders to change the values of the integers that you are adding. To show the solution, select "Show result" button

Nicholas F. Bennett, Created with GeoGebra




Integer Subtraction

This sketch is the accompanying sketch to integer addition. As an educator, I know that it can be frustrating when students mix up the signs when adding or subtracting integers. The goal for students in the activity is for them to determine sign of subtracting positive and negative integers together.

Integer Subtraction

This is a Java Applet created using GeoGebra from www.geogebra.org - it looks like you don't have Java installed, please go to www.java.com

Move the red and blue sliders to find the difference between two integers

Nicholas F. Bennett, Created with GeoGebra