Lesson 3 Ways to Look at Quadrilaterals

    • Let’s sort and identify quadrilaterals.

Warm-up How Many Do You See: Brick Pattern

How many bricks have 2 pairs of parallel sides?

image of brick tiles. please ask for further assistance.

Activity 1 Quadrilateral Hunt

  1. Find the quadrilaterals that have each of the following attributes. Record their letter names here.

    attribute

    quadrilaterals with the attribute

    no right angles

    one pair of parallel sides

    one pair of perpendicular sides

    same length for all sides

    same size for all angles

    same length for only two sides

    no parallel sides

    two obtuse angles

  2. Choose one sentence to complete based on your work.

    1. I noticed some quadrilaterals …

    2. I noticed that all quadrilaterals …

    3. I noticed that no quadrilaterals …

  3. If you have time… Do you think it is possible for a quadrilateral to have:

    • More than 2 acute angles?

    • More than 2 obtuse angles?

    • Exactly 3 right angles?

    If you think so, sketch an example. If you don’t think so, explain or show why you think it is impossible.

Activity 2 What’s True about These Quadrilaterals?

Here are four sets of quadrilaterals.

Quadrilaterals D and AA are squares

2 squares labeled D and A, A. all sides equal length. Opposite sides parallel. All angles right angles.

Quadrilaterals K, Z, and AA are rectangles.

3 rectangles K, Z, AA. all opposite sides parallel and same length. All have 4 right angles. Rectangle AA, all 4 sides same length.

Quadrilaterals N, U, and Z are parallelograms.

N, U, 2 pairs of parallel sides, 1 set one length, the other a different length, 2 obtuse angles and 2 acute angles the same size. Z, 4 sides, opposite pairs same length and parallel , 4 right angles.

Quadrilaterals AA, EE, and JJ are rhombuses.

3 rhombuses labeled AA, EE, JJ. all sides same length. Opposite sides parallel. Rhombus AA has 4 right angles.

Write 4–5 statements about the sides and angles of the quadrilaterals in each set. Each statement must be true for all the shapes in the set.

Square:

Rectangle:

Rhombus:

Parallelogram:

Activity 3 Guess Again

Partner A:

  • Write down an attribute that a quadrilateral could have. Don’t show it to your partner.

  • Find 3 quadrilaterals that have that attribute and 3 that don’t. Place them in the columns of the table.

Partner B:

  • Study the quadrilaterals chosen by your partner.

  • Pick another quadrilateral from the set. Ask: “Does this quadrilateral have the attribute?”

  • Find at least 1 quadrilateral that has the attribute and 1 that doesn’t.

  • Guess the attribute. If your guess is off, ask more questions before guessing again.

Switch roles after the attribute is guessed correctly.

    • Partner A’s attribute:

    have the attribute

    do not have the attribute

    • Partner B’s attribute:

    have the attribute

    do not have the attribute

Practice Problem

Problem 1

Here are 3 rhombuses:

3 rhombuses. all have opposite sides parallel and same length, opposite angles equal size. A, B, 2 acute, 2 obtuse angles. C, 4 right angles.

  1. What attributes do the rhombuses share?

  2. What attributes are different in the three rhombuses?