Unit 1.3 student notes Surface Areas of Objects Made from Right Rectangular Prisms.notebook
September 19, 2013
Aug 24­4:22 PM
Review
Sep 12­11:21 AM
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Unit 1.3 student notes Surface Areas of Objects Made from Right Rectangular Prisms.notebook
September 19, 2013
Area
square
rectangle
parallelogram
triangle
circle
Sep 12­4:34 PM
What is surface area?
How do you find the surface area?
• draw a net
• find the area of each face
• add all areas together
Sep 12­4:35 PM
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Unit 1.3 student notes Surface Areas of Objects Made from Right Rectangular Prisms.notebook
September 19, 2013
Formulas to remember:
SA of rectangle:
Sep 12­4:35 PM
Example:
Find the surface area of the box.
20 cm
10 cm
10 cm
Sep 12­4:39 PM
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Unit 1.3 student notes Surface Areas of Objects Made from Right Rectangular Prisms.notebook
September 19, 2013
Aug 24­4:23 PM
Aug 24­4:26 PM
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Unit 1.3 student notes Surface Areas of Objects Made from Right Rectangular Prisms.notebook
September 19, 2013
Aug 24­4:27 PM
Two strategies to find the surface area of a composite object created with linking cubes:
1) Multiply the number of cubes by 6 and subtract two times the number of overlaps
(6 x number of cubes) ­ (2 x number of overlaps)
2) Draw all the views then count the total number of squares in all six views of the object.
Sep 12­4:54 PM
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Unit 1.3 student notes Surface Areas of Objects Made from Right Rectangular Prisms.notebook
September 19, 2013
method 1:
method 2:
4
Top Bottom- 4
Front - 4
Back - 4
Left - 3
Right - 3
Total = 22 cubes2
Aug 24­4:29 PM
Find the surface area of the object:
4 cm
Rectangle 1: Top & Bottom= 4 x 5 x 2 = 40
Front & Back = 10 x 4 x 2 = 80
Left & Right = 10 x 5 x 2 = 100
5 cm SA=220 cm2
10 cm 1
2
12 cm 5 cm
Rect. 2: Top & Bottom= 12 x 5 x 2 = 120
Front & Back = 12 x 5 x 2 = 120
Left & Right = 5 x 5 x 2 = 50
SA= 290 cm2
Overlap x 2 = 4 x 5 x 2 = 40 cm2
Total SA = SA rect.1 + SA rect. 2 - overlap
= 220 + 290 - 40 = 510 - 40 = 470 cm2
Sep 12­5:03 PM
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Unit 1.3 student notes Surface Areas of Objects Made from Right Rectangular Prisms.notebook
September 19, 2013
Do pages 30­31 # 4,5, 8,10,11
Sep 16­3:12 PM
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