Geometry: An Interactive Journey to Mastery



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we humans could probably not detect the difference. Many would then say that it seems reasonable to

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Lesson 23

1. 3 hh + 3h = 100 gives h ௘6HHFigure S.23.1௘ͽ


2. The area of the base is^12 ˜˜ 23 3.

(^) 12 12 12 36.
36 2 3 36 2 3.
36 63.

LA

SA

V



u 

u

௘6HHFigure S.23.2௘ͽ

3. The area of one face is  8 5. So,^12 ˜˜ s giving s 52.


4. D௘ͽ 6HHFigure S.23.3.

(^)   
21.
21 9 30.
(^13)     
h
LA rs
SA
V

SS

SS S

SS





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5. 33 x gives xV 33 3, so 33 3 3.௘6HHFigure S.23.4௘ͽ

3

4

h^3

Figure S.23.1

6

2

22

Figure S.23.2

7

3

h

Figure S.23.3

3 x

2 x

x

x

x

Figure S.23.4