14

Using the TI-73: A Guide for Teachers

Patterns and Relations

Activity

Have students perform the steps unless otherwise indicated.

1.Model the wall using toothpicks to represent the beams to a length of 6.

2.As each length of the wall is modeled, record the total number of beams in a T-chart.

Example

 

 

 

length(X)

 

number of

 

 

 

 

beams(Y)

 

 

 

 

1

 

4

2

 

7

3

 

10

4

 

13

5

 

16

6

 

19

7

 

22

 

 

 

 

3.Investigate the pattern in the tables and concrete models and predict how many beams are needed for a wall length of 7 and a length of 10.

4.Record answers in the table and share in small groups how these values were determined.

5.With students working in small groups, ask them to write a sentence to describe the patterns they see in the table.

Ask: Do these patterns make sense in terms of the concrete model?

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