4.6 Quick Graphs Using Slope – Intercept Form
Algebra 1
4.6 QUICK GRAPHS USING SLOPE – INTERCEPT FORM
Example: On the coordinate plane below, graph and label each of these linear equations. Make a table if necessary.
(a) y = 2x
(b) y = 2x + 3
(c) y = 2x – 4
(d) y = 2x – 7
y
x
Example: Use the graphs above to complete the chart below.
Equation
y = 2x
y = 2x + 3
y = 2x – 4
y = 2x – 7
Slope
y – intercept
Example: What relationships between the equation and the slope and y – intercepts do you notice?
Example: Lines that have the same _________________ are parallel.
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4.6 Quick Graphs Using Slope – Intercept Form
Algebra 1
Slope Intercept Form
All the equations in the previous examples were in slope – intercept form.
Slope intercept form is ______________________________.
(x, y) are _________________________________________________________________________.
m is the __________________________.
b is the ___________________________.
To graph an equation in slope – intercept form, plot the ___________________________________, and use the
_________________________ to find at least ________ other points.
Example: Given the equation y = –2x + 3, what is the slope? What is the y – intercept?
Example: Given the equation y = 12 −
Example: Graph the equation y = −
3
x , what is the slope? What is the y – intercept?
4
1
x+3.
4
y
x
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4.6 Quick Graphs Using Slope – Intercept Form
Algebra 1
Standard Form
Not all linear equations are written in slope – intercept form. In fact, many are written in standard form. Standard
form is when all the variables are on the left side and constant terms are on the right side. To graph these, we can
put them in slope – intercept form by _____________________________________________________________.
Example: Rewrite the equation in slope – intercept form.
–2x + y = –4.
Example: Rewrite the equation in slope – intercept form.
2x + 3y = 12
Example: Graph the last two examples on the same coordinate plane. Where do they intersect?
y
x
For more help, visit http://www.chaoticgolf.com, go to TUTORIALS, then Graphing Lines in Slope-Intercept Form.
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