Lesson 1-6Lesson 1-6

PolygonsPolygons

Ohio Content Standards:

Ohio Content Standards:

• Formally define geometric

figures.

Ohio Content Standards:

• Use coordinate geometry to represent and examine the properties of geometric

figures.

Ohio Content Standards:

• Make and test conjectures about characteristics and properties (e.g., sides, angles, symmetry) of two-dimensional figures and three-dimensional objects.

Vocabulary

Vocabulary

Polygon:

Vocabulary

Polygon:A closed

figure formed

by a finite number

of segments

Vocabulary

Polygon:A closed

figure formed

by a finite number

of segments

Vocabulary

Concave:

Vocabulary

Concave:A

polygon that

“caves” in on itself.

Vocabulary

Concave:A

polygon that

“caves” in on itself.

Vocabulary

Convex:

Vocabulary

Convex:A

polygon that does not

“cave”

in.

Vocabulary

Convex:A

polygon that does not

“cave”

in.

Vocabulary

Convex:A

polygon that does not

“cave”

in.

Vocabulary

n-gon:

Vocabulary

n-gon:

A polygon with “n” sides.

VocabularyRegular

Polygon:

VocabularyRegular

Polygon:A convex polygon which all sides and angles are congruent.

Polygons:Number

of sides:

Polygons:Number

of sides:

3triangle

Polygons:Number

of sides:

4

quadrilateral

Polygons:Number

of sides:

5pentagon

Polygons:Number

of sides:

6hexagon

Polygons:Number

of sides:

7heptagon

Polygons:Number

of sides:

8octagon

Polygons:Number

of sides:

9nonagon

Polygons:Number

of sides:

10decagon

Polygons:Number

of sides:

12dodecagon

Name each polygon by the number of sides. Then classify it as convex or

concave, regular or irregular.

Name each polygon by the number of sides. Then classify it as convex or

concave, regular or irregular.

Name each polygon by the number of sides. Then classify it as convex or

concave, regular or irregular.

Vocabulary

Vocabulary

Perimeter:

Vocabulary

Perimeter:

The sum of the

lengths of the

polygons sides.

A masonry company is contracted to lay three layers of decorative brick along the foundation for a new house given the dimensions below.

A masonry company is contracted to lay three layers of decorative brick along the foundation for a new house given the dimensions below.

40 ft

36 ft

12 ft 24 ft

36 ft

30 ft

8 ft30 ft

A masonry company is contracted to lay three layers of decorative brick along the foundation for a new house given the dimensions below.

40 ft

36 ft

12 ft 24 ft

36 ft

30 ft

8 ft30 ft

Find the perimeter of the foundation and determine how Find the perimeter of the foundation and determine how many bricks the company will need to complete the job. many bricks the company will need to complete the job.

Assume one brick is 8 inches long.Assume one brick is 8 inches long.

A masonry company is contracted to lay three layers of decorative brick along the foundation for a new house given the dimensions below.

40 ft

36 ft

12 ft 24 ft

36 ft

30 ft

8 ft30 ft

The builder realizes he accidentally halved the size of The builder realizes he accidentally halved the size of the foundation, so he reworks the drawing with the the foundation, so he reworks the drawing with the

correct dimensions. How will this affect the perimeter of correct dimensions. How will this affect the perimeter of the house and the number of bricks needed?the house and the number of bricks needed?

Find the perimeter of pentagon ABCDE with A(0, 4), B(4, 0), C(3, -4), D(-3, -4),

and E(-3, 1).

Find the perimeter of pentagon ABCDE with A(0, 4), B(4, 0), C(3, -4), D(-3, -4),

and E(-3, 1).

The width of a rectangle is 5 less than twice the length. The

perimeter is 80 centimeters. Find the length of each side.

Assignment:

Pgs. 49 - 50 12-34 evens, 40-44 evens