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7th Grade Math / Lesson 6B: Polygons II

What will we be learning in this lesson?

  • In this lesson, you will learn about the different types of quadrilaterals.
Vocabulary words are found in this purple color throughout the lesson. Remember to put these in your notebook.


  • Quadrilaterals are polygons with 4 sides. Below is a venn diagram that displays how the different quadrilaterals are related to each other.


  • Remember, overlapping sections means that there are things in common between those shapes. And if the shapes do not overlap or touch at all, then they do not have anything in common with each other.


  • Since all parts of the venn diagram are inside of the quadrilateral section, this means that all of these shapes are Quadrilaterals.


  • Since the trapezoid part and the parallelogram part do not touch at all, that means that they are two different types of quadrilaterals.


  • The square section overlaps with the rectangles and the rhombuses. This means that squares have the same characteristics as both rectangles and rhombuses.


  • Using the definitions of the different quadrilaterals, look at how they are set up in the venn diagram and how the shapes are related to each other.

    Trapezoid : a quadrilateral with only one pair of parallel sides.

    Parallelogram : a quadrilateral with opposite sides that are parallel and equal in length.

    Rhombus : a quadrilateral with OPPOSITE sides parallel and ALL sides equal in length.


    Rectangle : a quadrilateral with OPPOSITE sides parallel and equal in length with only right angles.

    Square : a quadrilateral with OPPOSITE sides parallel, ALL sides equal in length, and only having right angles.

    Notice the definition of the square is similar to the definitions of rhombus and rectangle.

  • Can you differentiate between the types of quadrilaterals?
  • Go back to the classroom to get to your homework and any other items you need to attend to.