Practice 3­6: Slope­Intercept Form
Name ______________________________________
Complete the table of x­ and y­coordinates. Graph the line. Use the graph to find the slope and y­intercept.
1. x
y = 3x  2
( x , y )
−2
3−2   2 = −6  2 = −4
−2 ,−4 
0
1
slope: ________
y­intercept: ( 0 , )
2. x
y=
3
x1
2
( x , y )
−4
0
2
slope: ________
y­intercept: ( 0 , )
3. x
1
y =− x − 4
3
( x , y )
−6
0
3
slope: ________
y­intercept: ( 0 , )
4. What is the relationship between a line's slope, y­intercept, and equation?
5. Now you can write the equation of any line if you know the slope and the y­intercept...
y=mxb ...where m is the ______________ and (0 , b) is the ________________________. This is called the _____________________________________________ of a line.
6. Now that you have learned how to identify the slope and y­intercept of a line, the next step is to write its equation.
y
Use the graph of the line on the left to complete the following:
Find the slope of the line (rise over run). slope = _______
x
What is the y­intercept of the line? ( 0 , )
Equation of the line: y= ______________ 7. Now suppose you were given an equation and told to graph its solutions without making a table. Well, you only need to know the slope and y­intercept to graph the line. Begin by plotting the y­intercept, then use the slope to find another point on the line. Remember, slope is “rise over run”.
a. y = 2 x − 3
y
slope = _______ y­int: _______
b. x − 2 y = 6 (Hint: Solve for y first.)
slope = _______ y­int: _______
x