Lesson 7 slope intercept form.notebook
February 05, 2016
Lesson 7 (PH Text 5.3): Slope­Intercept Form y=mx+b
Objective: to write linear equations using slope intercept­form to graph linear equations in slope intercept­form
Parent Function – the simplest function with certain characteristics
Linear Parent Function – the simplest linear function – y = x
Linear Equation – an equation that models a linear function – the highest power of x in a linear function is 1
y­intercept – the y­coordinate of a point where the graph crosses the y­axis
Feb 2­8:26 AM
Slope­Intercept Form of an equation => y = mx + b
slope
y-intercept
What are the slope and y­intercept of the line for each equation?
y = 3x – 5
Feb 2­8:27 AM
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Lesson 7 slope intercept form.notebook
February 05, 2016
Write the equation of a line with the given slope and y­intercept.
b = ­5
b = 0
Feb 2­8:30 AM
Write the equation of a line with the given slope and y­intercept.
m = 0, b = ­2
Feb 2­8:31 AM
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Lesson 7 slope intercept form.notebook
February 05, 2016
Test the coordinates of a point to see if the point lies on a particular line. Substitute the x­ and y­coordinates to see if they make the equation true.
Does the point (2, 4) lie on the line with the equation y = 3x – 6 ?
____ = 3(____) – 6
Does the point (3, 3) lie on the line with the equation y = 3x – 6 ?
Feb 2­8:32 AM
To graph a linear equation: ① Plot the y­intercept ② Use the slope to count up and over to plot another point. ③ Draw your line. Then check for other points using the slope to verify them.
Graph the equation y = 3x – 1
y-intercept (b):
slope (m):
Feb 2­8:33 AM
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Lesson 7 slope intercept form.notebook
February 05, 2016
Graph the equation y-intercept:
slope:
Feb 2­8:35 AM
Rewrite an equation if it is not in slope­intercept form. Then graph the line.
Rewrite ­5 = 4x – y so it is in y = mx +b form.
Feb 2­8:36 AM
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Lesson 7 slope intercept form.notebook
February 05, 2016
Re­write: Feb 2­8:38 AM
Homework:
pg. 310
#'s 7­21 odd, 39, 37­40 all
Period 8 also do pg. 311 #'s 51 ­ 55
Feb 2­8:42 AM
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Lesson 7 slope intercept form.notebook
February 05, 2016
To write an equation for a line from a graph, get the slope and y­intercept from the graph and substitute into the form y = mx +b.
1. Find the y­intercept.
b = _____
2. Find the slope using two points.
m = _____
3. Substitute into y = mx + b to write the equation for the line
Feb 2­8:41 AM
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