Graph using Slope-Graph using Slope-Intercept FormIntercept Form

ReviewReviewWhat are two ways you find the slope of a What are two ways you find the slope of a

line?line?Slope formulaSlope formula

Plotting points and finding the rise and run Plotting points and finding the rise and run between pointsbetween points

Now let’s see another way to Now let’s see another way to graph a linegraph a line

Slope-Intercept FormSlope-Intercept Form

y = y = mmx + x + bb

When the equation is in this form, you can When the equation is in this form, you can identify the identify the slope (slope (mm)) and the and the y-intercept (y-intercept (bb))..

slopeslope y-intercepty-intercept

ExamplesExamples Identify the slope and y-interceptIdentify the slope and y-intercept

43 xy

23 yx

m = 3m = 3

m = -3m = -3

b = 4b = 4

b = 2

If the equation is not setup like y = mx + b, then you must manipulate the equation to that format. The general steps include:

-Add/Subtract your x value

-Multiply/Divide both sides of the equation by the coefficient of y

Do these examples on your Do these examples on your own paperown paper

1233 yx 64 yx

m = 1 b = -4

slope y-intercept slope y-intercept

m = -¼ b = 2

3

Graph the equation 2x + y = 3Graph the equation 2x + y = 3

Step 1: Rewrite the equation in slope-intercept form

y = -2x + 3

Step 2: Identify the slope and the y-intercept

m = -2 b = 3

Step 3: Plot the point that corresponds to the y-intercept

Step 4: Use the slope to locate a second point on the line. Draw a line through the two points.

y-intercept - (0,3)

Quiz time!!!!Quiz time!!!!

Take everything off your desk and Take everything off your desk and get ready for the quiz!get ready for the quiz!