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length of John’s cake?
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Fͽ ,QJHQHUDOZKDWLVWKHVLGHOHQJWKRIDVTXDUHZLWKWKHVDPHDUHDDVDQa × bUHFWDQJOH"ͼ7KLVTXDQWLW\
is called the geometric mean of a and bͽ
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the parallelogram?
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DQJOHVRI
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Dͽ
30°
(^22)
4
4
Figure 21.8
Eͽ
10 10
8
Figure 21.9