Contributor: Marlene Vogel. Lesson ID: 11283
Are you lost when it comes to using a compass? A geometry compass, that is! They can be used to draw basic math constructions, and even artwork! Ms. Mars shows you step-by-step steps to creative fun!
Compass Artwork
Let's disprove that notion.
Download the Compass Artwork document from Downloadable Resources in the right-hand sidebar. By the time you finish this lesson, your creative juices will be flowing!
Take a moment to look at the document.
Don't do anything yet, just look.
Now, it's time to get started!
Below is a list of vocabulary words that you need to be familiar with for this lesson.
The purpose of this lesson is to continue to add to your geometry vocabulary, help you become familiar with how to use a compass and a straightedge, and teach you how to draw the four basic constructions.
Before you begin drawing any of the constructions, it is important for you to understand the different parts of a compass and how to use it.
Above is a picture of a geometry compass.
Notice that this geometric tool has a point on the end of one leg, a pencil inserted into the other leg, and a knob where the pencil is inserted.
Also, notice that the compass has a black handle sticking out from the top. The two legs of a compass have the ability to spread farther apart or come closer together.
Use your own compass to see how easy it is to make the legs farther apart, then bring them closer together (Note: the point on the one leg can hurt, so avoid touching it.).
When you are getting ready to use your compass to draw a construction, you should go through a couple of steps:
The following information contains the four basic constructions — and short activities with each — so you can try working with your compass. Before starting the activity, discuss with your teacher the definitions of segment and ray.
Congruent Segments
This basic construction activity will help you learn how to draw two congruent segments:
Congruent Angles
This basic construction will teach you how to draw two congruent angles:
Perpendicular Bisector
This basic construction will teach you how to draw a perpendicular bisector for a segment:
Angle Bisector
This last construction will show you how to draw an angle bisector and split the angle into two congruent angles:
The following Got It? section offers activities for you to practice your new skills.