From Parallelograms to Triangles


Activity #1

Decompose Parallelograms into Triangles.

In this activity, you are going to use the applet below to decompose a parallelogram into triangles. Follow the instructions.

  • Draw a line to decompose each polygon into two identical triangles using the tool.
  • If you choose to, you can also draw the triangles using the tool.
  • Answer the questions below.

Activity #2

In continuation of decomposing a parallelogram into triangles, you are required here to break down the figure into triangles that are congruent (identical to each other.) Use the applet below for this exercise.

Decompose Parallelograms into Identical Triangles. 

  • On the grid, draw at least three different quadrilaterals that can each be decomposed into two identical triangles with a single cut.​
  • Use the line tool to show the cut line.
  • Answer the questions below.

Quiz Time

The quiz below can be completed at After a trial practice, click on our subscription link in the video, to see how much you’ll save when you signup from our website.