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Two Numbers Under the Microscope printable sheet

Microscope

Choose any two odd numbers, such as 5 and 9. Add them together.

Draw a picture or make a model to show how the numbers add together.

Adam found some dominoes with 5 and 9 spots on them:

One domino with 3 and 2 spots and another with 6 and 3 spots.

Sarai made a model using Multilink cubes:

One row of five cubes above another row of nine cubes.

Abdul drew a picture of 5 add 9 like this:

The number 5 represented as a row of 2 squares above a row of 3 squares. Joined to the right of this is the number 9 represented by a row of 5 squares above a row of 4 squares. The two shapes together form a rectangle.

What do you notice about the answer?

Look closely at the models and pictures. 

Can you see anything in any of them that would work in exactly the same way if you used two different odd numbers?

Can you use your one example to prove what will happen every time you add any two odd numbers?

See if you can explain this to someone else. Are they convinced by your argument?

Once you can convince someone else, see if you can find a way to show your argument. You might draw something or take a photo of things you have used to prove that your result is always true from your example.