Chapter 10 Straight lines and quadratic equations L
- Slides: 8
Chapter 10 Straight lines and quadratic equations
L 2: STRAIGHT LINES GRADIENT LO 2: Find the gradient of a straight line from the graph LO 5: Calculate the gradient of a line using co-ordinates of points of the line Theory: WAYS to find the gradient: 1. USING GRAPH: gradient = (y-change) / (x-increase) 2. USING CO-ORDINATES OF 2 POINTS (co-ordinates found from the table or graph of a straight line): gradient= (y. B – y. A) / (x. B – x. A) Ch 10: Straight lines and quadratic equations 2
L 2: STRAIGHT LINES GRADIENT LO 2: find the gradient of a straight line graph Practice: Calculate the gradient of each line (a) to (i). Leave your answer as a fraction in its lowest form. Ch 10: Straight lines and quadratic equations 3
L 2: STRAIGHT LINES GRADIENT LO 5: Calculate the gradient of a line using co-ordinates of points of the line Practice: 1. Calculate the gradient of the line that passes through both points. Leave your answwer as a whole number or a fraction in its lowest terms. A (-1, -4) and B(-3, 2). 2. If the car climbs 60 m vertically, how fast must the car have travelled horizontally? Ch 10: Straight lines and quadratic equations 4
L 2: STRAIGHT LINES FINDING THE EQUATION OF A STRAIGHT LINE LO 3: recognise and determine the equation of a line using slope-intercept form y=mx+c Practice: 1. Rearrange the equation so that it is in a form y = mx + c. Then find the gradient and y-intercept of each graph: (a) 4 x-y= 2 (b) 2 x – 6 – y = 0 (c) x= y/3 - 2 2. Find the equation (in a slope-intercept form ) of a line which has: (a) a gradient of -0, 75 and y-intercept of -0, 5 (b) a gradient of 0 and y-intercept at (0, -2) (c) a y-intercept of 6 and a gradient of -1/5 3. Find the equation of the line which passes through points A(-1, -3) and B(8, -7) 4. Find the equation of the line Ch 10: Straight lines and quadratic equations 5
L 2: STRAIGHT LINES FINDING THE EQUATION OF A STRAIGHT LINE LO 4: determine the equation of the line parallel to a given line (IGCSE textbook p. 194/6 – 9) Ch 10: Straight lines and quadratic equations 6
L 1: STRAIGHT LINES GRADIENT LO 2: find the gradient of a straight line graph Practice: Write down the gradient of each line shown in the diagram: Ch 10: Straight lines and quadratic equations 7
L 2: STRAIGHT LINES INTERSECTION WITH THE x-axis AND THE y-axis LO : not defined Theory. To find the x-intercept: put y=0 in the equation of the line To find the y-intercept: put x=0 in the equation of the line Practice: 1. Find the x-axis and the y-axis intercept for each of the following lines: (a) (b) x = 3 y – 0, 75 2. Find the y-intercept, if the given point lies on the graph (a) y = -2 x + c (-3, 3) (b) 2 x -3 y = d (2, 5) Ch 10: Straight lines and quadratic equations 8