Presentation on theme: "Identifying a Linear Equation from a Table of Values"— Presentation transcript:
1 Identifying a Linear Equation from a Table of Values Slope-Intercept Method
2 The tasks at hand Identify the slope of a line Identify the intercept of a lineJust what is the intercept of a line?
3 The diagram to the right shows both the X-intercept and the Y-intercept of the linear equation Y = -2X + 4As you can see, for the relation Y = -2x + 4, the X-intercept is (2, 0) and the Y –intercept is (0, 4).
4 Y = MX + BTo use a table of values, we must calculate both the slope and Y-intercept.To accomplish this, we will always use the Slope-Intercept Formula (Y = MX + B)M stands for the slope.B stands for the Y-intercept.Once we have completed this, we will have the equation.So let’s begin!
5 Calculating SlopeSlope = the change in Y (the rise) as X is increased by 1 (the run)Note the changes in the Y valuesIncreased by 2 every time while the values for X increase by 1Therefore, slope will beor simply 2. Therefore M = 2.XY-2-3-11325
6 Calculating The Y-Intercept Now select one pair of coordinates.Let’s use (2, 5) for this exampleWe could have chosen any of themInsert this ordered pair and M intoY = MX + BThen solve for B
7 M = 2Y = MX + B5 = (2)(2) + B5 = 4 + B5 – 4 = 4 – 4 + B1 = BSo, the equation will be Y = 2X + 1
8 Another example This time, Y is changing by 3 every time So M = 3 2158311414This time, Y is changing by 3 every timeSo M = 3Let’s use (2, 8)Y = MX + B8 = (3)(2) + B8 = 6 + B8 – 6 = 6 – 6 + B2 = BY = 3X + 2