3.  Right Triangle – A triangle with one right angle.  Hypotenuse – Side opposite the right angle and longest side of a right triangle.  Leg – Either of the two sides that form the right angle. Leg Hypotenuse

4.  In a right triangle, if a and b are the measures of the legs and c is the measure of the hypotenuse, then a 2 + b 2 = c 2.  This theorem is used to find the length of any right triangle when the lengths of the other two sides are known. b a c

5.  Example 1: Find the length of the hypotenuse of a right triangle if a = 3 and b = 4. 4 3 c a 2 + b 2 = c 2

6.  Example 2: Find the length of the leg of the following right triangle. 9 12 a a 2 + b 2 = c 2 __________________

7.  Example 3: Find the length of the hypotenuse c when a = 11 and b = 4. Solution Solution 11 4 SOLUTION c

8.  Copy this triangle into your maths books.  Complete using the Pythagoras’ Theorem formula. C 12 10