1. Warden 2006 To find the gradient of lines perpendicular to each other.

2. Warden 2006 Finding the Midpoint 1 2 3 6 9 5 8 4 7 Starter (We’re going to use this later)

3. Warden 2006 These lines are perpendicular

4. Warden 2006 PERPENDICULARMEANS AT RIGHT ANGLES

5. Warden 2006 What is each gradient? 2 1 Gradient = ½ 2 1 Gradient = -2

6. Warden 2006 What is each gradient? 3 1 Gradient = 3 3 1 Gradient = - 1 / 3

7. Warden 2006 THE GRADIENT OF A PERPENDICULAR LINE IS THE NEGATIVE RECIPROCAL OF THE OTHER

8. Warden 2006 What is the gradient of the lines perpendicular to these? y = 2x + 1 y = 3x + 2 y = 2 + 4x y + 2x = 2 2y = 3x - 2 5y + 2x = 3 m = 2 m = 3 m = 4 m = -2 m = 3 / 2 m = -2 / 5 -1 / m = -1 / 2 -1 / m = -1 / 4 -1 / m = -1 / 3 -1 / m = 1 / 2 -1 / m = -2 / 3 -1 / m = 5 / 2

9. Warden 2006 Write down an equation of a line perpendicular to these: y = 2x + 1 y = 3x + 2 y = 2 + 4x y + 2x = 2 2y = 3x - 2 5y + 2x = 3

10. Warden 2006 THE PRODUCT OF GRADIENTS OF PERPENDICULAR LINES IS EQUAL TO -1 Exercise 5E Question 1

11. Warden 2006 Two points A(1,2) and B(-3,6) are joined to make the line AB. Find the equation of the perpendicular bisector of AB