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normally, used in a right angled triangleto calculate the value of a missing side converse, use the three sides to see if the triangle is right angled Converse is used when the elements of a proposition are reversed. Hit - OK below We know this, because c is the hypotenuse (longest side). e.g.1. A triangle has sides 8cm, 11cm and 5cm. Is it right angled? If the triangle is right angled, then c2 = a2 + b2. c2 = a2 + b2 2 = 52 + 2 e.g.1. A triangle has sides 8cm, 11cm and 5cm. Is it right angled? If the triangle is right angled, then c2 = a2 + b2. Calculator: 112 = 52 + 82 c2 = a2 + b2 = (52 + 82 =) e.g.1. A triangle has sides 8cm, 11cm and 5cm. Is it right angled? If the triangle is right angled, then c2 = a2 + b2. Incorrect statement, the triangle is not right angled. Correct statement, the triangle is right angled. 121 = 89 112 = 52 + 82 c2 = a2 + b2 We know this, because c is the hypotenuse (longest side). e.g.2. A triangle has sides 12cm, 20cm and 16cm. Is it right angled? If the triangle is right angled, then c2 = a2 + b2. c2 = a2 + b2 2 = 122 + 2 e.g.2. A triangle has sides 12cm, 20cm and 16cm. Is it right angled? If the triangle is right angled, then c2 = a2 + b2. Calculator: 202 = 122 + 162 c2 = a2 + b2 = Incorrect statement, the triangle is not right angled. Correct statement, the triangle is right angled. e.g.2. A triangle has sides 12cm, 20cm and 16cm. Is it right angled? If the triangle is right angled, then c2 = a2 + b2. 400 = 400 202 = 122 + 162 c2 = a2 + b2 We know this, because c is the hypotenuse (longest side). If the values form a Pythagorean triad, then c2 = a2 + b2. e.g.3. Is 8, 15 and 17 a Pythagorean triad? c2 = a2 + b2 2 = 82 + 2 If the values form a Pythagorean triad, then c2 = a2 + b2. Calculator: e.g.3. Is 8, 15 and 17 a Pythagorean triad? 172 = 82 + 152 c2 = a2 + b2 = If the values form a Pythagorean triad, then c2 = a2 + b2. Incorrect statement, it is not a Pythagorean triad. Correct statement, it is a Pythagorean triad. e.g.3. Is 8, 15 and 17 a Pythagorean triad? 289 = 289 172 = 82 + 152 c2 = a2 + b2 A triad (or triple) is Pythagorean, if the 3 valuesform a correct statement when substitutedinto c2 = a2 + b2. A triangle is right angled if the 3 side lengthsform a correct statement when substitutedinto c2 = a2 + b2. The converse of Pythagoras' Theorem |