Geometry: An Interactive Journey to Mastery

Lesson 22: Explorations with Pi

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why, imagine that we have two circles, one of radius r and

the other of radius kr for some number k.

First, approximate each circle as a union of 12 congruent

triangles, as shown in )LJXUH.

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with scale factor k.

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SHULPHWHURIWKHOHIW¿JXUH

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agree every time?

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to-diameter ratio for the two original circles would still be the same for each?

r

kr

Figure 22.19