MG 3.0
Students demonstrate understanding of plane and solid
geometric objects and use this knowledge to show relationships
and solve problems.
UNDERLYING SKILLS AND CONCEPTS:
vocabulary
Classify Polygons
A polygon is a closed figure with straight sides.
a
K
ey Ide
Polygons have at least three angles and at least three sides.
polygons
not polygons
A polygon is named by the number of sides it has.
E x am p l E
1
How many sides and angles does a
quadrilateral have?
E x am p l E
2
Name these figures.
Explain how you know.
Look at the pictures above.
A quadrilateral has 4 sides
and 4 angles
Remember:
An angle is formed by the
intersection of 2 lines.
Polyg
o
mean n
s
many
angle
s.
page 290
A
B
C
Figure A and B are quadrilaterals
because they both have 4 sides.
C is a hexagon because
it has 6 sides.
Chapter 25 – Lesson 1
D – © CSL Associates, Inc. All rights reserved.
Name: Triangle Square Rectangle Quadrilateral Pentagon Hexagon Octagon
Number
4
4
4
5
8
6
of sides: 3
Name
P RAC T I C E
Tell why each of these figures is not a polygon.
1.
2.
Possible answer:
Possible answer: All of
This figure is not closed.
the sides are not straight.
Complete each sentence.
3. A triangle is shown in figure
C
4. A quadrilateral is shown in figure
B
5. A pentagon is shown in figure
D
6. A hexagon is shown in figure
A
D – © CSL Associates, Inc. All rights reserved.
7. An octagon is shown in figure
F
A
B
E
D
F
C
Draw each polygon.
8. Triangle
Math
Reasoning
9. Hexagon
Geometry
10. Pentagon
MR 1.1
11. Draw this polygon on the grid paper.
I have 4 sides.
2 of my sides are parallel.
2 of my sides are not parallel.
Chapter 25 – Lesson 1
page 291
MCX94.HW.CL.G4.FM&Lesson.v211
8/2/04
19:16
Page 194
Name
…at home!
P RAC T I C E
Tell why each of these figures is not a polygon.
1.
2.
The figure does not have
This figure is not closed.
straight sides.
Complete each sentence.
3. A triangle is shown in figure
D
.
4. A quadrilateral is shown in figure
C
.
5. A pentagon is shown in figure
F
.
6. A hexagon is shown in figure
B
.
A, E
.
A
C
B
E
D
Draw each polygon.
8. Quadrilateral
Math
Reasoning
9. Pentagon
Geometry
10. Octagon
MR 1.1
11. Draw this polygon on the grid paper.
I have 5 sides.
2 of my sides are parallel.
3 of my sides are not parallel.
Answers may vary.
page 194
Home Resource and Homework
Chapter 25 Lesson 1
D – © CSL Associates, Inc. All rights reserved.
F
7. An octagon is shown in. figure
MCX94TEG4Ch01_32.v8.5.2 2/26/01 19:05 Page 535
Name
P RAC T I C E
Tell why each of these figures is not a polygon.
1.
2.
Possible answer:
Possible answer: All of
This figure is not closed.
the sides are not straight.
Complete each sentence.
3. A triangle is shown in figure
C
4. A quadrilateral is shown in figure
B
5. A pentagon is shown in figure
D
6. A hexagon is shown in figure
A
D – © CSL Associates, Inc. All rights reserved.
7. An octagon is shown in figure
F
A
B
E
D
F
C
Draw each polygon.
8. Triangle
9. Hexagon
Answers may vary.
Answers may vary.
Math
Reasoning
10. Pentagon
Geometry
Answers may vary.
MR 1.1
11. Draw this polygon on the grid paper.
I have 4 sides.
2 of my sides are parallel.
2 of my sides are not parallel.
Chapter 25 – Lesson 1
Student Book Page
A
page 291
Name
…at home!
P RAC T I C E
Tell why each of these figures is not a polygon.
1.
2.
The figure does not have
This figure is not closed.
straight sides.
Complete each sentence.
3. A triangle is shown in figure
D
.
4. A quadrilateral is shown in figure
C
.
5. A pentagon is shown in figure
F
.
6. A hexagon is shown in figure
B
.
A
C
B
E
D
F
A, E
.
Draw each polygon.
8. Quadrilateral
9. Pentagon
Answers may vary.
Math
Reasoning
Answers may vary.
Geometry
10. Octagon
Answers may vary.
MR 1.1
11. Draw this polygon on the grid paper.
I have 5 sides.
2 of my sides are parallel.
3 of my sides are not parallel.
Answers may vary.
page 194
Home Resource and Homework
Chapter 25 Lesson 1
D – © CSL Associates, Inc. All rights reserved.
7. An octagon is shown in. figure