There are many quadrilaterals in these ... figures? All quadrilaterals have 4 sides
and 4 angles. ... Write the type of quadrilateral that best describes the shape.
10-8
MAIN IDEA
Quadrilaterals
There are many quadrilaterals in these fields. How can you describe some of the different figures?
I will identify, describe, and classify quadrilaterals.
New Vocabulary rectangle square rhombus parallelogram trapezoid
All quadrilaterals have 4 sides and 4 angles.
KEY CONCEPT
Quadrilaterals
A rectangle has 4 right angles, with opposite sides equal and parallel. A square has 4 right angles, with opposite sides parallel. All sides are equal in length. A rhombus has 4 equal sides and opposite sides are parallel.
These marks show equal sides.
A parallelogram has opposite sides equal in length and parallel. A trapezoid has at least 1 pair of parallel sides.
EXAMPLE
Classify a Quadrilateral
1 Classify the quadrilateral in as many ways as possible. It can be classified as a parallelogram, rectangle, square, and rhombus.
410
Chapter 10 Geometry
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Many real-world objects have the shapes of quadrilaterals.
Real-World EXAMPLES
Real-World Shapes
2 VIDEO GAMES Write the type of quadrilateral that best describes the game controller. The game controller has one pair of parallel sides. So, it has the shape of a trapezoid. 3 Identify the shape outlined in the sculpture. The opposite sides of the shape are equal and parallel. So, the shape is a parallelogram. Personal Tutor at ca.gr4math.com
Classify each quadrilateral in as many ways as possible. See Example 1 (p. 410)
1.
2.
trapezoid 3.
rhombus and parallelogram
square, rectangle, rhombus, and parallelogram
Write the type of quadrilateral that best describes the shape. See Examples 2–3 (p. 411)
4.
7.
trapezoid
5.
square
How are a square and a rhombus alike? How are they Sample answer: different? They both have 4 equal sides. A square has right angles. Extra Examples at ca.gr4math.com
0410-0413_CH10L8-105711.indd 411
rectangle6.
Lesson 10-8 Quadrilaterals 411
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EXTRA
% )# E # T4 IC !C 2A 0R P
See page R27.
Classify each quadrilateral in as many ways as possible.
parallelogram
See Example 1 (p. 410)
rectangle 9. and parallelogram
8.
trapezoid
11.
12.
trapezoid
10.
square, rectangle, rhombus, and parallelogram
13.
rectangle and parallelogram
Write the type of quadrilateral that best describes the shape. See Examples 2 and 3 (p. 411)
14.
square
15.
17.
trapezoid
18.
rectangle
rectangle
16.
rectangle 19.
trapezoid 20. A quadrilateral has 4 sides with opposite sides parallel and 4 right angles. Two sides are longer than the others. What is the quadrilateral?
rectangle
21. Phillip draws a quadrilateral. It has all 4 sides the same length. Its opposite sides are parallel. What quadrilateral did he draw? rhombus
22. OPEN ENDED Draw two quadrilaterals that can be classified as parallelograms. See Ch. 10 Answer Appendix. REASONING Tell whether each statement is true or false. 23. A rhombus is a square false 25.
412
24. A rectangle is a parallelogram true
True or false: All squares are rectangles, but not all rectangles are squares. Explain. See Ch. 10 Answer Appendix. Chapter 10 Geometry
