Gradient and y intercept of a Staightline.pptx

IGCSE Gradient and y intercept of a Staightline.pptx

1. Chapter 15 The equation of a straight line

2. x -5 -4 -3 -2 -1 0 1 2 3 4 5 6 y 4 3 2 1 -1 -2 -3 -4 A B C D F H Starter What is the Sign of the gradient of each line

3. Objectives   Find out y-intercept and gradient of a straight line Change of a line equation in the form of Find the equation of straight line  

4. y = m x + c The equation of any straight line is of the form: Gradient (steepness) y-intercept (where is crosses the y-axis) Introduction

5. Form of a straight line   Gradient ‘steepness or slope’ y-intercept Where the graph crosses the y-axis When x = 0, what is y? y-intercept

6. Objective 1 Find gradient and y-intercept of the lines A) y = 3x +4 B) y = 2x -5 C) D) 2y = 4x +10 E)y = 1 – 2x  

7. Activity 2. Find the gradient and y-intercept of the following lines: a) y = 3x + 7 b) y = -4x - 3 c) y = 9 – 3x d) y – 2x = 5 gradient = 3 y-intercept =7 gradient = - 4 y-intercept = - 3 gradient = - 3 y-intercept = 9 gradient = 2 y-intercept = 5 y = 2x + 5

8. Objective 2 Change the equation in the form of A) B) 4x+4y = 15 C) x -5y = 40  

9. Activity 2 Convert into y= mx+c form * 3x+4y =24 ** 7x +10y = 30 *** 10x = 5y+28

10. Objective 3. Find the equation of a line

11. For 1 along the x-axis Increase of 2 up the y-axis Gradient of 2 Crosses y-axis at 3 y = 2 x + 3 y = m x + c Gradient crosses y-axis

12. For 1 along the x-axis Increase of 3 up the y-axis Gradient of 3 y = m x + c Gradient crosses y-axis Crosses y-axis at 2 y = 3 x + 2

13. For 1 along the x-axis Increase of 5 up the y-axis Gradient of 5 y = m x + c Gradient crosses y-axis Crosses y-axis at 1 y = 5 x + 1 change in y change in x Gradient =

14. For 1 along the x-axis Increase of 4 up the y-axis Gradient of 4 Crosses y-axis at 4 y = 4 x + 4 y = m x + c Gradient crosses y-axis change in y change in x Gradient =

15. For 1 along the x-axis Increase of 2 up the y-axis Gradient of 2 Crosses y-axis at -1 y = 2 x - 1 y = m x + c Gradient crosses y-axis change in y change in x Gradient =

16. Activity 2: Pg no. 264 Q.2 and Q4

17. HOT: More practice : Find Gradient and y – intercept of given lines e) 5y = 15x + 20 f) e) 6y + 12x = 24 g) 11y + 5x = -4 h) 6y – 3x + 36 = 0 gradient = 3 y-intercept = 4 y = 3x + 4 gradient = - 2 y-intercept = 4 6y = - 12x + 24 y = - 2x + 4 gradient =   y-intercept =   11y = - 5x - 4 y = - x -   gradient =   y-intercept = - 6 6y = 3x - 36 y = x - 6  

18. Plenary…. Exit Ticket: What is the relationship shared by y- inercept and gradient of a line

19. H. W. and TDN Do the quiz https://api.mangahigh.com/en/px/251/0/0 H.W. Page no 266 and 267 Q2 or Q3 and from Q4 and 6 choose any 2 sub questions Solving equation graphically