# Geometer’s Sketchpad Sketches at Sketch Exchange

Before I became a GeoGebra user, I used The Geometer’s Sketchpad. I migrated to GeoGebra because aside from it is free, it is more friendly to students. Geometer’s Sketchpad requires a little mathematical maturity and knowledge of geometric constructions. I still like Geometer’s Sketchpad,  GeoGebra is getting and better.

Last month, I have shared to you more than 12000 free dynamic applets from GeoGebraTube and more than a year ago, I have also mentioned more than 7000 demonstrations from Wolfram. To add to the list of dynamic geometry resources, The Geometer’s Sketchpad has also created its library of “sketches” in Sketch Exchange.  Sketch Exchange as of this writing has more than 500 sketches available.  Just like GeoGebraTube and Wolfram Demonstrations, it is a place where GSP users can share sketches, tips, and tutorials.

Most of the sketches in Sketch Exchange requires Geometer’s Sketchpad 5.05, a free upgrade if you have Sketchpad 5.

# Geometer’s Sketchpad Essentials 8 – Rotating Geometric Objects

This is the eighth tutorial in the Geometer’s Sketchpad Essentials Series.  In this post we are going to learn the Rotate command. First we are going to create a triangle and name it ABC, create a center of rotation point D, and then rotate a triangle 90 degrees.

The output of this tutorial is shown in the first figure. Continue reading

# Geometer’s Sketchpad Essentials 7 – Translating Geometric Objects

This is the sixth part of the Geometer’s Sketchpad Tutorial Series.  In this post, we are going to learn how to use the Translate command.   First, we are going to make a translation vector using two points A and B, where A is the initial and B is the terminal point. We are going to construct a triangle and translate it using vector AB.

Instructions

1. Using the Point tool construct two points and use the Text tool to reveal their names. Be sure that they are named  A and B. Continue reading

# Geometer’s Sketchpad Essentials 5 – Basic Graphing

This is the fifth part of the Geometer’s Sketchpad Essentials Series.  In this post, we are going to learn how graph using Geometer’s Sketchpad. We are going to plot the function $f(x) = x^2$ and $g(x) = x + 1$, change their properties such as colors, and thickness, and plot their intersections.

The output of our tutorial is shown above. To construct the graph, follow the step by step  instructions below.  Continue reading

# Geometer’s Sketchpad Essentials 4 – The SSS Triangle Congruence

This is the fourth part of the Geometer’s Sketchpad Essentials Series. In this tutorial, we are going to construct another triangle which is congruent to a given triangle using the concept of the SSS triangle congruence.  Recall that the SSS congruence theorem tells us that two triangles are congruent, if their corresponding sides are congruent. In doing the construction, we are going to learn how to use the Ray tool, the Circle tool, and other commands.

1.) Construct triangle ABC.

2.) Next, we construct ray DE.  To do this, click the Straightedge tool box and hold the mouse button to display the other tools. Now, choose the Ray tool.

3.) Click two distinct points on the sketch pad and display the names of the two points. Your sketch should look like the first figure.

4.) Next, we will construct a segment DF which is congruent to AC. To do this, be sure to deselect all the objects by clicking on the vacant part of the sketch pad. Select point D, then select segment AC (do not select the points!), click the Construct menu, and then click Circle By Center+Radius. This will produce a circle with center D and radius equal to the length of AC. Continue reading