Session 2, Part B:

In This Part: Constructing Triangles | Constructing Quadrilaterals | Properties of Triangles

This activity requires the Flash plug-in, which you can download for free from Macromedia's Web site. For a non-interactive, hands-on version of this activity, use linkage strips (or make your own strips).

Problem B6

Fill in the table below. Use this linkage-strip Interactive Activity (or the hands-on version) to try to build quadrilaterals with the given lengths. Write "yes" or "no" in the fifth column of the table to indicate whether or not you can make a quadrilateral from those four lengths. Experiment with different sets of lengths. When you build a quadrilateral, see if you can deform it into a different quadrilateral with the same side lengths. When you click "Show Answers," the filled-in table will appear below the problem. Scroll down the page to see it.

Side A

Side B

Side C

Side D

Is it a quadri-
lateral?

Can it be deformed?

 4 units 4 units 4 units 4 units 4 units 3 units 2 units 2 units 3 units 2 units 1 unit 1 unit 4 units 1 unit 2 units 1 unit

Here is the table filled in for the quadrilaterals with given lengths and for other sample quadrilaterals.

Side A

Side B

Side C

Side D

Is it a quadri-
lateral?

Can it be deformed?

 4 4 4 4 Yes Yes 4 3 2 2 Yes Yes 3 2 1 1 Yes Yes 4 1 2 1 No N/A 1 1 1 4 No N/A 2 2 2 2 Yes Yes 1 4 3 1 Yes Yes 1 3 3 4 Yes Yes 2 3 4 1 Yes Yes 4 1 1 2 No N/A

 Problem B7 For some of the lengths above, can you connect them in a different order to make a different quadrilateral? If so, which ones? How is this different from building triangles?

 Problem B8 Come up with a rule that describes when four lengths will make a quadrilateral and when they will not. Write down the rule in your own words. (You may want to try some more cases to test your rule.)

 Problem B9 Can a set of four lengths make two different quadrilaterals?

 Linkage-strip problems adapted from IMPACT Mathematics Course, 1, developed by Education Development Center, Inc. pp. 55-56, © 2000 Glencoe/McGraw-Hill. Used with permission. www.glencoe.com/sec/math
 Session 2: Index | Notes | Solutions | Video