7-5 Graphing linear equations

• Objectives: Graph linear equations by using the x and y intercepts or the slope and y intercept

Questions

•What are the x and y intercepts?•What equation form is it easiest to find the x and y intercepts?•How do you determine the x and y intercepts?•When the equation is in slope intercept form how do you easily graph the equation

• (Intercepts are the points where the line crosses the axes)

Since two points determine a line, we can use the intercepts to graph.

Graph the line 2x+4y=8

Set x to 0 and solve for y.

Now solve for x by setting y to 0

When the equation is in standard form (ax+by=c) complete the following:

When equations are in slope intercept form :y=mx+b…

• Identify the y intercept by setting x to “0”

• Plot the y intercept

• Identify a second point by plotting the slope. You do this by starting at your y intercept point.

y=-1/3x +4