NAME:
CLASS PERIOD:
Determining Slope and y-Intercept
The slope of a line is a measure of its tilt, or slant.
The slope of a straight line is a constant ratio, the “rise over run,” or the vertical change over
the horizontal change.
You can find the slope of a line by comparing any two of its points.
The vertical change is the difference between the two y-values, and the horizontal change is
the difference between the two x-values.
The y-intercept is the point where the line crosses the y-axis.
A. Find the slope of the line shown.
point A: (3, 2)
point B: (4, 4)
42
43
2
 , or 2
1
slope 
So, the slope of the line is 2.
B. Find the y-intercept of the line shown.
The line crosses the y-axis at (0, 4).
So, the y-intercept is 4.
Find the slope and y-intercept of the line in each graph.
1.
2.
slope m  _________________
slope m  _________________
y-intercept b  _________________
y-intercept b  _________________
Show any work on a separate sheet. DO NOT clutter this page with your figuring. Use
your notes and textbook (Pages 95-97) if you need help.
Find the slope and y-intercept of the line in each graph.
1.
2.
slope m  _________________
slope m  _________________
y-intercept b  _________________
y-intercept b  _________________
Find the slope and y-intercept of the line represented by each table. (Hint: △y ÷ △x)
3.
x
y
0
3
6
9
12
10
19
28
37
4.
x
y
0
2
4
6
8
2
3
4
5
slope m  _________________
slope m  _________________
y-intercept b  _________________
y-intercept b  _________________
Find and interpret the rate of change and the initial value. (Hint: page 96)
5. A pizzeria charges $8 for a large cheese pizza,
plus $2 for each topping. The total cost for a large
pizza is given by the equation C  2t  8, where t is
the number of toppings. Graph the equation for
t between 0 and 5 toppings, and explain the meaning
of the slope and y-intercept.
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________________________________________________
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Graphing Linear Nonproportional Relationships Using Slope
and y-Intercept
You can graph a linear function by graphing the y-intercept of the line and then using the
slope to find other points on the line.
The graph shows y  x  2.
To graph the line, first graph the y-intercept which is located
at (0, 2).
1
, from the y-intercept,
1
rise 1 and run 1 to graph the next point.
Because the slope is 1 or
Connect the points with a straight line.
Graph each equation using the slope and the y-intercept.
1. y  4x  1
slope  _____ y-intercept  _____
3. y  x  1
slope  _____ y-intercept  _____
2. y  
1
x2
2
slope  ____ y-intercept  _____
4. y  2x  3
slope  ____ y-intercept  _____
Show any work on a separate sheet of paper. Use your textbook, pages 101 – 103, if
you have questions.
Graph each equation using the slope and the y-intercept.
1. y  2x 1
2. y 
slope  _______ y-intercept  _______
3. y  x  4
1
x3
2
slope  _______ y-intercept  _______
4. y  x  2
slope  _______ y-intercept  _______
slope  _______ y-intercept  _______
**BONUS** Plus 10 for all parts completed correctly!
5.The equation y  15x  10 gives your score
on a math quiz, where x is the number of
questions you answered correctly.
a. Graph the equation.
b. Interpret the slope and y-intercept of the line.
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c. What is your score if you answered 5 questions correctly?