Difference between revisions of "Ptolemy's Theorem"
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[[File:Ptolemy's_Theorem.png]] | [[File:Ptolemy's_Theorem.png]] | ||
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+ | The key construction step is (b), which allows us to form 2 pairs of similar triangles: | ||
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+ | Examining the similar triangles in (c), we have <math>\frac{j}{d} = \frac{b}{p}</math>, so <math>jp = bd</math> | ||
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+ | Examining the similar triangles in (d), we have <math>\frac{j}{c} = \frac{a}{q}</math>, so <math>jq = ac</math> | ||
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+ | So <math>j(p+q) = bd + ac</math> ... Q.E.D. | ||
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+ | This theorem rests upon: | ||
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+ | [[File:InscribedAngle.gif]] |
Latest revision as of 16:42, 14 January 2016
The key construction step is (b), which allows us to form 2 pairs of similar triangles:
Examining the similar triangles in (c), we have , so
Examining the similar triangles in (d), we have , so
So ... Q.E.D.
This theorem rests upon: