Explore

We know that a quadrilateral has four sides. It is obvious that all of quadrilaterals in the picture are not parallelograms. So I wonder how can we use our knowledge of the properties of a parallelogram to decide which quadrilaterals are parallelograms.

Go to Geogebra: Proving Parallelograms. Choose two of the cases given. For each case you choose:

  • Decide if enough information is given to prove the quadrilateral is a paralelogram (yes or no)
  • State the case as a rule. (For example, if a quadrilateral has two pairs of sides with equal slopes....)
  • Explain why, using theorems and properties given in earlier lessons and units.

Submit your two paragraphs to the 5.03 Explore Dropbox.

At the end of this lesson, student will be able to:

  • Prove quadrilaterals are parallelograms including coordinate geometry.

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