6th Grade Math Textbook, Fundamentals

WX

Z Y

17 cm

30

 10 cm

Lesson 9-11 for exercise sets. &KDSWHU 

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Classify each quadrilateral by giving the name that best describes it.

For exercises 5–6, is the statement true? Write always, sometimes, or never.

5.A square is a rhombus.

6.In a parallelogram, all sides are congruent and all angles are congruent.

7.Find the missing lengths and angle measures

for parallelogram WXYZ.

8.Discuss and Write Write a paragraph describing the relationships among

quadrilaterals, trapezoids, parallelograms, rectangles, rhombuses, and squares.

Some quadrilaterals have several names.

The figure at the right can be classified as:

• a parallelogram because it has 2 pairs of parallel lines


• a kite because it has 2 pairs of adjacent congruent sides


• a rhombus because it is a parallelogram with 4 congruent sides


• a rectangle because it is a parallelogram with
  4 right angles


• a square because it is a parallelogram with
  4 right angles and 4 congruent sides
  The figure is best described as a
  square because that name gives the
  most specific information.

The concept map shows the

relationships among quadrilaterals.

Note that all rhombuses are kites,

but not all kites are rhombuses.

Use properties of quadrilaterals to find missing side

and angle measures.

ABCDis a parallelogram. What is the measure

of BCD? What is the measure of side AB?

Opposite angles and opposite sides of

parallelograms are congruent.

BCDis opposite BAD, so BCDBAD.

ABis opposite CD, so ABCD.

So mBCD42° and the length of ABis 5 cm.

quadrilateral

trapezoid parallelogram

rectangle

square

rhombus

kite

8.5 cm

5 cm

42°

BC

AD