10-9 Surface Area Course 1 Warm Up Warm Up Lesson Presentation Lesson Presentation Problem of the Day Problem of the Day
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
10-9 Surface Area
Course 1
Warm UpWarm Up
Lesson PresentationLesson Presentation
Problem of the DayProblem of the Day
Warm UpIdentify the figure described.
1. two parallel congruent faces, with the other faces being parallelograms
2. a polyhedron that has a vertex and a face at opposite ends, with the other faces being triangles
prism
pyramid
Course 1
10-9 Surface Area
Learn to find the surface areas of prisms, pyramids, and cylinders.
Course 1
10-9 Surface Area
Vocabulary
surface areanet
Insert Lesson Title Here
Course 1
10-9 Surface Area
The surface area of a three-dimensional figure is the sum of the areas of its surfaces. To help you see all the surfaces of a three-dimensional figure, you can use a net. A net is the pattern made when the surface of a three-dimensional figure is layed out flat showing each face of the figure.
Course 1
10-9 Surface Area
Additional Example 1A: Finding the Surface Area of a Prism
Find the surface area S of the prism.
Method 1: Use a net.
Draw a net to help you see each face of the prism.
Use the formula A = lw to find the area of each face.
Course 1
10-9 Surface Area
Additional Example 1A Continued
A: A = 5 2 = 10
B: A = 12 5 = 60
C: A = 12 2 = 24
D: A = 12 5 = 60
E: A = 12 2 = 24
F: A = 5 2 = 10
S = 10 + 60 + 24 + 60 + 24 + 10 = 188Add the areas of each face.
The surface area is 188 in2.
Course 1
10-9 Surface Area
Additional Example 1B: Finding the Surface Area of a Prism
Find the surface area S of each prism.
Method 2: Use a three-dimensional drawing.
Find the area of the front, top, and side, and multiply each by 2 to include the opposite faces.
Course 1
10-9 Surface Area
Additional Example 1B Continued
Front: 9 7 = 63
Top: 9 5 = 45
Side: 7 5 = 35
63 2 = 126
45 2 = 90
35 2 = 70
S = 126 + 90 + 70 = 286 Add the areas of each face.
The surface area is 286 cm2.
Course 1
10-9 Surface Area
Check It Out: Example 1A
Find the surface area S of the prism.
Method 1: Use a net.
Draw a net to help you see each face of the prism.
Use the formula A = lw to find the area of each face.
3 in.11 in.
6 in. 11 in.
6 in. 6 in.3 in.
3 in.
3 in.
3 in.
A
B C D E
F
Course 1
10-9 Surface Area
Check It Out: Example 1A
A: A = 6 3 = 18
B: A = 11 6 = 66
C: A = 11 3 = 33
D: A = 11 6 = 66
E: A = 11 3 = 33
F: A = 6 3 = 18
S = 18 + 66 + 33 + 66 + 33 + 18 = 234
Add the areas of each face.
The surface area is 234 in2.
11 in.
6 in. 6 in.3 in.
3 in.
3 in.
3 in.
A
B C D E
F
Course 1
10-9 Surface Area
Check It Out: Example 1B
Find the surface area S of each prism.
Method 2: Use a three-dimensional drawing.
Find the area of the front, top, and side, and multiply each by 2 to include the opposite faces.
6 cm 10 cm
8 cm
topfront side
Course 1
10-9 Surface Area
Check It Out: Example 1B Continued
Side: 10 8 = 80
Top: 10 6 = 60
Front: 8 6 = 48
80 2 = 160
60 2 = 120
48 2 = 96
S = 160 + 120 + 96 = 376 Add the areas of each face.
The surface area is 376 cm2.
6 cm 10 cm
8 cm
topfront side
Course 1
10-9 Surface Area
The surface area of a pyramid equals the sum of the area of the base and the areas of the triangular faces. To find the surface area of a pyramid, think of its net.
Course 1
10-9 Surface Area
Additional Example 2: Finding the Surface Area of a Pyramid
Find the surface area S of the pyramid.S = area of square + 4 (area of
triangular face)
S = 49 + 4 28
S = 49 + 112
Substitute.
S = s2 + 4 ( bh) 12__
S = 72 + 4 ( 7 8)12__
S = 161The surface area is 161 ft2.
Course 1
10-9 Surface Area
Check It Out: Example 2
Find the surface area S of the pyramid.
S = area of square + 4 (area of triangular face)
S = 25 + 4 25
S = 25 + 100
Substitute.
S = s2 + 4 ( bh) 12__
S = 52 + 4 ( 5 10)12__
S = 125The surface area is 125 ft2.
5 ft
5 ft
10 ft
10 ft
5 ft
Course 1
10-9 Surface Area
Lesson Quiz
Find the surface area of each figure. Use 3.14 for .
1.rectangular prism with base length 6 ft, width
5 ft, and height 7 ft
2. Find the surface area of the figure shown.
Insert Lesson Title Here
Course 1
10-9 Surface Area
214 ft2
208 ft2
Related Documents
