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Parent Graph: Simplest function of a family of functions with common characteristics. 5.4 Point-Slope Form:. Linear Parent Function: is y = x or f(x) = x. Linear Equation: is an equation that models a linear function. Y-intercept: The point where the graph crosses the y-axis. GOAL:.
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Parent Graph: Simplest function of a family of functions with common characteristics. 5.4 Point-Slope Form: Linear Parent Function: is y = x or f(x) = x. Linear Equation: is an equation that models a linear function. Y-intercept: The point where the graph crosses the y-axis.
Whenever we are given a graph we must be able to provide the equation of the function. Point-Slope Form: The linear equation of a nonvertical line with slope m and a point (x1, y1) is: y-y1 = m(x-x1) Y value of given point. X value of given point. Slope = =
Where does - = m(-) come from: Slope = Definition of Slope The variable we use for slope Slope = m Let be any point on the line and substitute () for () = m = m Isolate - =m(x) Point-Slope form.
EX: Provide the equation of the line that passes through (8, -4) and has a slope of 2/3
SOLUTION: Provide the equation of the line that passes through (8, -4) and has a slope of 2/3 Given: slope = point: (8, -4) m = (8, -4) = (x1, y1) =m(x) =(x) Substitute point
=(x) =(x) (-)(-) = + =x Distribute slope Isolate y =x Common denominator = x
Graph: = x b = -9.3 Slope up 2 right 3
YOU TRY IT:Provide the equation of the line that passes through (3, 2) and has a slope of 4/9
YOU TRY IT: (Solution) Provide the equation of the line that passes through (3, 2) and has a slope of 4/9 Given: slope = point: (3, 2) m = (3, 2) = (x1, y1) =m(x) =(x) Substitute point
=(x) =x Distribute slope Isolate y =x Common denominator = x
Graph: = x b = = 0.66 Slope up 4 right 9
CLASSWORK:Page 316-317 Problems: 2, 3, 5, 8, 11,
HOW TO GRAPH POINT-SLOPE FORM: We can graph this equation by looking at the given information within the equation. EX: Graph y – 1 = (x – 2)
Use the given point and slope: Graph y – 1 = (x – 2) We can see from the equation that Point (2,1) Slope m= Two up Three right.
YOU TRY IT:Graph the following equation: y – 4 = - (x + 3)
Use the given point and slope: y – 4 = - (x + 3) We can see from the equation that Point (-3 ,4) Opposite of what we see! Slope m=- Down one right two.
CLASSWORK:Page 316-317 Problems: 12, 13, 14, 15
USING TWO POINTS TO WRITE THE POINT-SLOPE FORM: Provide the point-slope equation of the line that passes through (-2, -3) and (1, 4)
In order to provide the point-slope equation of the line that passes through (-2, -3) and (1, 4) we must: 1. Find the slope m = m = m = 2. Use one of the given points (either one) =(x) Choosing: (1, 4) =(x) Choosing: (-2, -3)
YOU TRY IT: Provide the point-slope equation of the line that passes through (6, -2) and (-1, 3)
In order to provide the point-slope equation of the line that passes through (6, -2) and (-1, 3) we must: 1. Find the slope m = m = m = - 2. Use one of the given points (either one) =-(x) Choosing: (6, -2) =- (x) Choosing: (-1, 3)
CLASSWORK:Page 316-317 Problems: 19, 20, 21,
WRITING THE POINT-SLOPE FORM FROM A TABLE: Provide the point-slope equation shown by the following data:
Use two data points to find the rate-of-change (slope): m = m = m = Use the equation with a point, say (70, 490) =(x)
YOU TRY IT: Provide the point-slope equation shown by the following data:
Use two data points to find the rate-of-change (slope): m = m = m = Use the equation with a point, say (70, 490) =(x)
VIDEOS: Graphs https://www.khanacademy.org/math/algebra/linear-equations-and-inequalitie/point-slope-form/v/idea-behind-point-slope-form https://www.khanacademy.org/math/algebra/linear-equations-and-inequalitie/point-slope-form/v/linear-equations-in-point-slope-form
CLASSWORK:Page 316-317 Problems:As many as needed to master the concept