day 2 scale drawings
TRANSCRIPT
Scale Figures On Core.notebook
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April 09, 2013
Do Now
AIM: Scale
A A, C, and EB B, C, and DC B, E, and FD A, B, and E
Scale Figures On Core.notebook
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April 09, 2013
A blueprint is a technical drawing that usually displays architectural plans. Pete's blueprint shows a layout of a house. Every 4 inches in the blueprint is 3 feet in the actual house. One of the walls in the blueprint is 24 inches long. What is the actual length of the wall?
16in
24in
A.) Complete the table to find the actual length of the wall.
Blue Print (in) 4 8 12 16 20 24
Actual length(ft) 3 6
Scale Figures On Core.notebook
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April 09, 2013
1a. In Pete's blueprint the length of a side wall is 16 inches. Find the actual length of the wall
1b. The back wall of the house is 33feet long. What is the length of the back wall in the blueprint?
1c. How do you know your answer to 1b is reasonable?
Scale Figures On Core.notebook
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April 09, 2013
A Scale drawing is a proportional two-dimensional drawing of an object. Scale drawings can represent objects that are smaller or larger than the actual object.
Scale Figures On Core.notebook
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April 09, 2013
• A Scale is a ratio between 2 sets of measurements. It shows how dimensions in a scale drawing is related to the actual object.
• Scales are usually shown as two numbers separated by a colon such as 1:20 or 1cm:1m. Scales can be shown in the same unit or different units.
• You solve scale-drawings problems by using PROPORTIONAL REASONING
Scale Figures On Core.notebook
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April 09, 2013
The figure at the right is a scale drawing of a large rectangular room. What is the are of the actual room?
10cm
7cm
2cm = 5m
Scalea.) Find the number of meters represented by 1cm in the drawing.
1cm in this drawing is equal to ____m in the actual room.
Scale Figures On Core.notebook
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April 09, 2013
The figure at the right is a scale drawing of a large rectangular room. What is the are of the actual room?
10cm
7cm
2cm = 5m
Scaleb.) Find the actual length of the room labeled 7cm in the drawing.
The length of the side labeled 7 cm represents _____m.
Scale Figures On Core.notebook
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April 09, 2013
The figure at the right is a scale drawing of a large rectangular room. What is the are of the actual room?
10cm
7cm
2cm = 5m
Scalec.) Find the actual length of the room labeled 10cm in the drawing.
The length of the side labeled 10 cm represents _____m.
Scale Figures On Core.notebook
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April 09, 2013
The figure at the right is a scale drawing of a large rectangular room. What is the are of the actual room?
10cm
7cm
2cm = 5m
Since are is length times width, the area of the actual room is:
_____m X ______ m = ______ m2
Scale Figures On Core.notebook
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April 09, 2013
2a.) Find the length and width of the actual room, then find the area of the room. Round your answer to the nearest tenth. 6.5in
5in
3in:8ft
2b.) How can you solve 2 without having to determine the number of meters represented by 1cm?.
Scale Figures On Core.notebook
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April 09, 2013
In the scale drawing, assume the rectangle is drawn on centimeter grid paper. The scale is 1cm:3m.
x
y
Suppose you redraw the rectangele on a centimeter grid paper using the scale of 1cm:6m. In the new scale, 1cm represents more than/less than 1cm in the old scale
The measurement of each side of the new rectangle will be twice/half as long as the measurement of the original rectangle.
Scale Figures On Core.notebook
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April 09, 2013
B.) Draw the rectangle for the new scale 1cm:6m.
x
y
3a.) Find the actual length of each side of your original drawing using the old scale, 1cm = 3m. Find the actual length of each side of your new drawing using the new scale. How do you know your answers are correct?
Scale Figures On Core.notebook
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April 09, 2013
Homework
On Core Page 92 #1-4 all