Geometry Module 5, Topic E, Lesson 21

Students Learning

Student Outcomes

  • Students determine the area of a cyclic quadrilateral as a function of its side lengths and the acute angle formed by its diagonals.
  • Students prove Ptolemy’s theorem, which states that for a cyclic quadrilateral ABCD, AC·BD = AB·CD + BC·AD. They explore applications of the result.

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Common Core Learning Standards

CCLS State Standard
G.C.3 Construct the inscribed and circumscribed circles of a triangle, and prove properties of angles for...

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