Teacher resources and professional development across the curriculum

Teacher professional development and classroom resources across the curriculum

Monthly Update sign up
Mailing List signup
Learning Math Home
Patterns, Functions, and Algebra
Session 3 Part A Part B Part C Part D Part E Homework
Algebra Site Map
Session 3 Materials:

Session 3:
Other Kinds of Functions

In This Part: Functions and More Functions | More Functions | A Geometric Function

Sometimes, functions can be based on an algorithm but still not use numbers as inputs. Here's an algorithm; let's call it Algorithm M: Note 10


Start with a polygon


Find the midpoint of each side of the polygon


Connect each midpoint to the two midpoints on either side of it

Here's what the algorithm does to a pentagon:

pentagon algorithm

Take it Further

Problem E13


Try Algorithm M on three different triangles. Describe in words how the output is related to the input.

Be sure to select triangles that are different in a significant way: acute, obtuse, scalene, isosceles.   Close Tip


Problem E14


How does any new triangle created by Algorithm M relate to the original, in size and in shape?


Problem E15


Try Algorithm M on several different quadrilaterals. Describe anything you notice about the outputs.

As with Problem E13, select quadrilaterals that are different in a significant way. You might also concentrate on a specific type of special quadrilateral to determine if Algorithm M does something similar to all quadrilaterals of that type.   Close Tip


Problem E16


Does Algorithm M describe a function? Explain how you know.


Problems in Part E taken from IMPACT Mathematics Course 3, developed by Education Development Center, Inc. (New York: Glencoe/McGraw-Hill, 2000).

Next > Homework

Learning Math Home | Algebra Home | Glossary | Map | ©

Session 3: Index | Notes | Solutions | Video


© Annenberg Foundation 2017. All rights reserved. Legal Policy