1. Unit 9. Day 4.

2. So far we’ve noticed this pattern:
Scale factor: 2
10 m
10 m
5 m
5 m
4 m
4 m
2 m
2 m
40 𝑚 2 40
𝑚 2
10 𝑚 2 10
𝑚 2
14 m
28 m
2 1
2 1
2 1
4 1

3. You will tackle some (in my opinion) challenging problems that use this idea:
4 3
Scale factor:
Side
Area
Original
Scale Drawing
4 3
16 9
Groups of 4

4. Example A:Based on the drawing below, what will the area of the planned half-court be?
Scale Drawing: 1 in. on the drawing corresponds to 15 ft. of actual length
10 𝑚𝑖𝑛𝑢𝑡𝑒𝑠

5. Example A:Based on the drawing below, what will the area of the planned half-court be?
Scale Drawing: 1 in. on the drawing corresponds to 15 ft. of actual length
2 1 𝑖𝑛
5 3 𝑖𝑛 2 𝐴=
15 𝑓𝑡 1 𝑖𝑛
𝑙𝑒𝑛𝑡ℎ
2 𝑖𝑛
𝑤𝑖𝑑𝑡ℎ
𝑆𝑐𝑎𝑙𝑒 ( ):
𝑎𝑟𝑒𝑎
𝑠𝑖𝑑𝑒
10 3 𝐴=
𝑖𝑛 2
225 𝑓𝑡 𝑖𝑛 2
𝑆𝑐𝑎𝑙𝑒 (𝑎𝑟𝑒𝑎):
10 3
225 𝑓𝑡 𝑖𝑛 2 𝐴= ∙
𝑖𝑛 2
2250
𝑓𝑡 2 𝐴=
750 3

6. Example A:Based on the drawing below, what will the area of the planned half-court be?
Scale Drawing: 1 in. on the drawing corresponds to 15 ft. of actual length =
15 𝑓𝑡
𝑥 𝑓𝑡 𝐴=
30 𝑓𝑡
𝑙𝑒𝑛𝑡ℎ
25 𝑓𝑡
𝑤𝑖𝑑𝑡ℎ
1 𝑖𝑛
2 𝑖𝑛 𝐴=
750
𝑓𝑡 2 1𝑥 =
30 𝑓𝑡 30
15 𝑓𝑡 =
𝑥 𝑓𝑡
1 𝑖𝑛
5 3 𝑖𝑛 1𝑥 =
25 𝑓𝑡 25

7. Example B: The triangle depicted by the drawing has an actual area of 36 square units. What is the scale of the drawing?
(Note: Each square on the grid has a length of 1 unit.)
10 𝑚𝑖𝑛𝑢𝑡𝑒𝑠

8. Example B: The triangle depicted by the drawing has an actual area of 36 square units. What is the scale of the drawing? (Note: Each square on the grid has a length of 1 unit.) 6
1 2
Scale factor: 𝐴= 6 3
𝑏𝑎𝑠𝑒
ℎ𝑒𝑖𝑔ℎ𝑡
𝐴= 18 2 =9
𝐴𝑟𝑒𝑎
𝑆𝑖𝑑𝑒 3
𝑠𝑐𝑎𝑙𝑒 𝑑𝑟𝑎𝑤𝑖𝑛𝑔 𝑎𝑐𝑡𝑢𝑎𝑙 :
9 36
1 2 3 6 6

9. N/A Scale Factor 16 6 ? 48 𝑢𝑛𝑖𝑡𝑠 2 28 10 ? 140 𝑢𝑛𝑖𝑡𝑠 2 𝑠𝑚𝑎𝑙𝑙 𝑙𝑎𝑟𝑔𝑒 =
Base
Height
Perimeter
Area
Small
Large
Scale
Factor 16 6 ?
48 𝑢𝑛𝑖𝑡𝑠 2 28 10 ?
140 𝑢𝑛𝑖𝑡𝑠 2
N/A
𝑠𝑚𝑎𝑙𝑙 𝑙𝑎𝑟𝑔𝑒 =
4 7
3 5
48 140
? ?
24 70
12 35 10 6 16 28
Example C: