LESSON
Using Formulas in Geometry
1-5
Lesson Objectives (p. 36):
______________________________________________________________
______________________________________________________________
Vocabulary
1. Perimeter (p. 36): _______________________________________________
______________________________________________________________
2. Area (p. 36): ___________________________________________________
______________________________________________________________
3. Base (p. 36): ___________________________________________________
______________________________________________________________
4. Height (p. 36): __________________________________________________
______________________________________________________________
5. Diameter (p. 37): ________________________________________________
______________________________________________________________
6. Radius (p. 37): __________________________________________________
______________________________________________________________
7. Circumference (p. 37): ___________________________________________
______________________________________________________________
8. Pi (p. 37): ______________________________________________________
______________________________________________________________
Key Concepts
9. Perimeter and Area (p. 36):
RECTANGLE
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
SQUARE
TRIANGLE
17
Geometry
LESSON
Using Formulas in Geometry
1-5
Lesson Objectives (p. 36):
apply formulas for perimeter, area, and circumference.
______________________________________________________________
______________________________________________________________
Vocabulary
the sum of the side lengths of a figure.
1. Perimeter (p. 36): _______________________________________________
______________________________________________________________
number of nonoverlapping square units of a given size that
2. Area (p. 36): the
___________________________________________________
exactly cover a figure.
______________________________________________________________
side of a triangle.
3. Base (p. 36): a
___________________________________________________
______________________________________________________________
segment from a vertex that forms a right angle with a line
4. Height (p. 36): a
__________________________________________________
containing the base.
______________________________________________________________
segment that passes through the center of a circle and
5. Diameter (p. 37): a
________________________________________________
whose endpoints are on the circle.
______________________________________________________________
`
segment whose endpoints are the center of a circle and a
6. Radius
(p. 37): a
__________________________________________________
point on the circle.
______________________________________________________________
distance around a circle.
7. Circumference (p. 37): the
___________________________________________
______________________________________________________________
the ratio of a circle’s circumference to its diameter, approximated
8. Pi (p. 37): ______________________________________________________
as 3.14.
______________________________________________________________
Key Concepts
9. Perimeter and Area (p. 36):
RECTANGLE
SQUARE
TRIANGLE
c
w
?
P 2l 2w or 2(l w)
A lw
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
h
s
a
b
P 4s
A s2
Pabc
1
bh
A 2bh or 2
17
Geometry
LESSON 1-5 CONTINUED
10. Circumference and Area of a Circle (p. 37):
11. Get Organized In each shape, write the formula for its area and perimeter.
(p. 37).
Triangle
Rectangle
Formulas
Circle
Square
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
18
Geometry
LESSON 1-5 CONTINUED
10. Circumference and Area of a Circle (p. 37):
The circumference C of a circle is given by the formula C d or
C 2r. The area A of a circle is given by the formula A r 2.
11. Get Organized In each shape, write the formula for its area and perimeter.
(p. 37).
Triangle
Rectangle
P 2 2w
A w
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
Formulas
1
A 2 bh
Square
Circle
P 4s; A s 2
C 2r
A r 2
18
Geometry