1. Trigonometry – Right Angled Triangles By the end of this lesson you will be able to identify and calculate the following: 1. Find the shorter side length of a right angled triangle

2.  Sometimes a question will give you the length of the hypotenuse and ask you to find the length of one of the shorter sides.  In such examples, we need to rearrange Pythagoras’ formula.

3.  Given that find c 2 = a 2 + b 2, we can rewrite this as:  a 2 = c 2 − b 2 or  b 2 = c 2 − a 2  It is easier to know what to do in this case if you remember that:  finding the length of a short side means subtract.

7.  Some questions will require you to decide which method is needed to solve the problem.  A diagram will help you decide whether you are finding the hypotenuse or one of the shorter sides.  On your diagram, check whether you are finding the length of the hypotenuse or one of the shorter sides.

8.  Exercise 8B-Finding the length of a shorter side  Questions 1-2 odd, 3, 5,8,9,11, 13