Graphing and Linear Functions: Practice Exercises
Here are various Exercises to accompany the section Graphing and Linear Functions. Some Exercises are designed to be done with a partner and to be graded by the
partner.
Arithmetic Operations and Lines
- Fill in the following chart and sketch the
corresponding linear function, f(x) = -3x
- 2:
Corresponding
Algebraic formula |
x |
x |
3x |
-3x |
-3x - 2 |
| Geometric Effect |
|
Take the graph
of the
identity function |
|
|
|
| Numerical Effect |
Take the input |
Apply the
identity function |
|
|
|
Numerical
Results |
Inputs |
Outputs |
| -1 |
|
|
|
|
| 0 |
|
|
|
|
| 1 |
|
|
|
|
Solution.
- Make up your own linear function, by filling in the
blanks, g(x) = __x + __. Note:
You can use positive or negative numbers, including fractions, in each slot.
Fill in the following chart and sketch a graph for your function.
Corresponding
Algebraic formula |
x |
x |
|
|
|
| Geometric Effect |
|
Take the graph
of
the identity function |
|
|
|
| Numerical Effect |
Take the input |
Apply the
identity function |
|
|
|
Numerical
Results |
Inputs |
Outputs |
| -1 |
|
|
|
|
| 0 |
|
|
|
|
| 1 |
|
|
|
|
Solution.
- Match each equation with the corresponding
graph. Hint: Use the geometric
description of linear equations given in the text.
 |
|
- y = -2x
- 1
- y = 1
- y = 2x
- 1
- y = -x
- 2
- x = 1
- y = x - 1
|
Solution.
The Equation of a Linear Function
- Using the description
of linear equations in the text, give a formula for each of the
following linear functions:
-
| x |
y = f(x)
|
-1
0
1
|
-4
-1
2
|
-
- b = p(m), where b
is the balance (in dollars) after m months
on an (interest-free) car loan of $5000 that your parents made you,
assuming that you pay them back $200 per month. Hint: Make
a table of values.
- F = q(C), where C
is the temperature in degrees Celsius and F
is the temperature in degrees Fahrenheit. Hint: When C
= 0, F = 32 (i.e., the freezing
point of water), and when the temperature goes up 1 degree Celsius, it
goes up 1.8 degrees Fahrenheit.
Solution.
-
Work with your partner to create more practice
Exercises.
- Have your partner choose his/her own linear function (cf. a previous
Exercise), and keep it hidden from you. Then have your partner
make a table of values at x
= -1, 0, 1, 2 for his/her function, and show it to you. Try to
guess your partner's function.
- Have your partner choose his/her own linear function (cf. a previous
Exercise), and keep it hidden from you. Then have your partner
make define a new function with this formula in XFunctions:
Try to guess your partner's function by looking only at its
graph.
- Have your partner imagine an applied situation similar to the ones given
in the text, where one quantity begins at a given amount and changes
as a multiple of some other quantity. Have him/her describe this
situation to you, and see if you can write down a correct equation.
Solution.
Modeling Linear Functions
- Using the concept of slope
in the text, determine which of the following represent linear functions,
and give a formula for those that are linear:
-
| x |
y = f(x)
|
5
10
15
|
7
2
-3
|
-
-
| x |
y = h(x)
|
1
-1
5
|
10
6
18
|
Solution.
- Work with your partner to create more practice
Exercises.
- Have your partner choose his/her own linear function (cf. a previous
Exercise), and keep it hidden from you. Then have your partner
make a table of values at four different inputs for his/her function, and show it to you. Try to
guess your partner's function.
- Have your partner choose his/her own linear function (cf. a previous
Exercise), and keep it hidden from you. Then have your partner
make define a new function with this formula in XFunctions:
Try to guess your partner's function by looking only at its
graph.
Solution.
Go to Pre-Composition and
Graphing .