CPM Student Tutorials

Side Lengths & Perimeter

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  • Click on the link below.
  • Drag the vertices of the rectangle.  Notice the changes of the side lengths and the perimeter.

CREATE: 5-sided pentagon

Modify the file:

  • Add a 5th point and sliders in the Points folder.
  • Add an additional side in the table.
  • Link the image "E" (found in the Images folder) to the 5th vertex.
CREATE: 5-sided pentagon

Modify the expressions and formulas found in the Calculations & Table folder.

  • Modify the "DA" formula to "DE" formula.
  • Add a "EA" formula.
  • Change the formula for the perimeter to reflect all 5 sides.
  • At the top, add the DE and EA formulas.
  • Verify your work!


Rename the file: Pentagons: Side Lengths and Perimeter

Save to your Desmos Account & save to your Google spreadsheet.

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