Math = Love: Recognizing Arithmetic Sequences as Linear Functions

## Saturday, March 18, 2017

### Recognizing Arithmetic Sequences as Linear Functions

As I posted before, this is my first year teaching sequences in Algebra 1.  The new Oklahoma math standards (OAS) include this standard:

A1.A.3.5 Recognize that arithmetic sequences are linear using equations, tables, graphs, and verbal descriptions. Use the pattern, find the next term.

I succeeded in using equations and graphs with my students.  I didn't have them make tables.  And, I should have included verbal descriptions.  I definitely have some room for improvement for next year.

I did exceed the standard by having students write a rule for the sequence that allowed them to find any term in the sequence.

My students were a bit confused at first when it came to how to graph the sequence on the coordinate plane.  Many students thought that our first point should be graphed on the y-axis.  Now that I think about it, having students make a table with "Term" and "Value" as the two columns would have taken care of this because it would have turned the sequence into a set of ordered pairs.  I will definitely add a table to these notes for next year!

We examined the graphed points to find the slope of the line.  This value went in front of x.  Then, we used the slope to determine where the line would cross the y-axis.  This gave us the rest of our rule.

After doing a couple of these together, many of my students were working ahead without any prompting from me.

My students would probably have been perfectly happy to make graphs in order to find the rule, but I decided to show them a method of finding the rule that doesn't require making a graph.

I first learned about the DINO method for finding the nth term of an arithmetic sequence from the Miss Brookes Maths blog.  A google search led me to this free worksheet and poster set from Numero Maths.

Almost all of my students ended up using this method on their quiz.  So, I guess my students found it useful.

The files for this lesson are on my school computer.  I will upload them as soon as I get back from Spring Break!

#### 6 comments:

1. Mathematics is the most beautiful and most powerful creation of the human spirit.
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2. Love! Files?

3. Would love to use this!! Do you have the files?!

4. Hey Sarah, it's the end of November 2017, Is Spring Break over? :D I love your materials and would love to use this very soon. Do you have the files uploaded somewhere else on your page? If so, will you please direct me to the correct page? Thanks for all you do!

5. Love these resources, do you have files for them?

6. Sarah is really good about tagging her posts, so you can always click the tags on the post to see if the files are posted in a different post about the same topic. Here is the link to the files she shows in this post.

Sarah, I'm more familiar with your blog at this point than I am with my textbooks. haha.