Name ____________________________________________________________________________________ Date _______________________
MOD 5 STUDY GUIDE
Use functions to model relationships between quantities
I can construct a function to model a linear relationship between two quantities.
I can determine the rate of change and initial value of the function.
I can interpret the rate of change and initial value of a linear function.
1) Use the graph to find the slope and y-intercept. Then write the equation of the line in slope-intercept
form.
slope, m = __________
y-intercept, b = __________
equation of the line: ______________________________
2) An oven starts heating from room
temperature, 68°F. To bake the salmon dinner
the oven must be 400°F. This takes place at a
rate of 20°F per minute. Write the equation
for the oven temperature t after m minutes?
3) Michael took out a $12,000 loan from his favorite
aunt to buy a fish aquarium. He makes a payment
of $300 every month. The table shows the
number of months, x, and the amount of money
Michael still has left to pay, y. Write an equation
in slope-intercept form to represent this situation.
Months, x
Debt left to pay, y
0
6
12
12,000 10,200 8,400
slope, m = __________
y-intercept, b = __________
equation of the line: _____________________________
Name:
Grade 8
Module 5
4) The graph shows how much money Baily is
saving each month in her bank account.
5) The lazer tag arena charges a $10 insurance
fee in addition to the $20 per hour playing fee.
The table shows the total cost, c, for renting a
surf board for h hours.
Hours, h
0
2
4
6
Total cost, c
10
50
90
130
a) What is the ordered pair of the y-intercept?
b) What does the y-intercept represent in this
situation?
a) What is the ordered pair of the y-intercept?
b) What does the y-intercept represent in this
situation?
6) A Christmas tree salesman earns $250 each
week, plus a commission for every tree he
sells. The table shows the total pay earned, y ,
in one week for the number of trees sold, x.
Write an equation in slope-intercept form to
represent this situation.
Trees sold, x
Total pay ($), y
4
6
8
350
400
450
a) Find the slope. m = __________
7) A line with a slope of 6 passes through the
point (2, 8).
a) Identify the y-intercept.
b) Write the equation of the line in slopeintercept form.
b) Identify the y-intercept. b = __________
c) Write the equation that represents this
situation in slope-intercept form.
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Name:
Grade 8
Module 5
8) What ordered pair represents the y-intercept
of the graph of y = -2x – 5?
10) Mariah Carey paid $192.55 for using 70
minutes of studio recording space in
September. In November she used 60
minutes and paid $170.
9) The table shows a linear relationship
between x and y. Write an equation in slopeintercept form for the relationship.
x
-2
-1
0
1
2
y
5
3
1
-1
-3
11) A line passes through the points (2, 2) and
(-3, -13).
a) Write the equation that represents this
situation in slope-intercept form.
a) Write the given ordered pairs.
(minutes, dollars)
b) Identify the y-intercept. b = __________
b) Find the slope.
m = __________
c) Find the y-intercept.
b = __________
d) Write the equation that represents this
situation in slope-intercept form.
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Name:
Grade 8
Module 5
Investigate patterns of association in bivariate data
I can interpret scatter plots for bivariate data to describe a linear or nonlinear association.
12) Use the graph to answer the questions.
13) Use the graph to answer the questions.
a) Does this graph show a linear
relationship?
a) Does this graph show a linear
relationship?
b) If the graph shows a linear relationship,
write the equation of the line that would
connect the set of data points. If the graph
does not show a linear relationship,
explain how you know.
b) If the graph shows a linear relationship,
write the equation of the line that would
connect the set of data points. If the graph
does not show a linear relationship,
explain how you know.
Page 4
Name:
Grade 8
Module 5
14) The table shows the length of a Super Rope after cutting it in half x amount of times.
36
18
9
4.5
a) Use the table to graph the data points.
c) If this is a linear relationship, write the
equation of the line that would connect the set
of data points. If the graph does not show a
linear relationship, explain how you know.
9
18
27
b) Is the relationship linear?
45
0
1
2
3
y
36
x
Length of
Super Rope
(in)
Length of rope (y)
Number of
cuts
1
2
3
4
5
Number of cuts (x)
15) The table shows the amount of money left on an iTunes gift card after x number of songs were
bought.
a) Use the table to graph the data points.
c) If this is a linear relationship, write the
equation of the line that would connect the
set of data points. If the graph does not show a
linear relationship, explain how you know.
10
20
b) Is the relationship linear?
40
y
47
44
41
38
30
x
2
4
6
8
50
Game
credits left
on card
Game Credits (y)
Number of
games
played
2
4
6
8
10
Number of games (x)
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