Unformatted text preview: ° . m( ∠ A) + m( ∠ B) = 90 ° since ABC has an angle sum of 180 ° . b x Let x = AD and let y = DB . Then, c = x + y . b a c y x a b By the (NIB) "Drop a Perpendicular" Theorem, there exists a point D on AB such that CD ⊥ AB . An argument involving the Exterior Angle Theorem proves that A - D - B. [ NTS: c 2 = a 2 + b 2 ] Proof: Given: Theorem 4.4.8 (The Pythagorean Theorem): In a right triangle, the square of the length of the hypotenuse is equal to the sum of the squares of the lengths of the other two sides. a b c D D D C B A C B A C B A C A B C...
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- Spring '10
- Pythagorean Theorem, Hypotenuse, triangle, BCD, aCD, Angle sum