Functions Review

Functions Test Review

What will be on the test?

• Vocabulary - match the words to their definition

• Determine whether a table, graph, or set of points is a function.

• Identify the constant rate of change and initial value in a table, graph, equation, or written description

• Compare the constant rate of change or initial value in two functions.

PART 1: Vocabulary

• function

• not a function

• constant rate of change

• initial value

Multiple Choice

Match the phrase to its definition: every input (x) has only ONE output (y)

• constant rate of change

• function

• not a function

• initial value

Multiple Choice

Match the phrase to its definition: the SLOPE in a linear relationship; it is the same no matter which points you use to find it

• constant rate of change

• function

• not a function

• initial value

Multiple Choice

Match the phrase to its definition: the STARTING AMOUNT or Y-INTERCEPT of the graph

• constant rate of change

• function

• not a function

• initial value

Multiple Choice

Match the phrase to its definition: some inputs (x) have MORE THAN ONE output (y)

• constant rate of change

• function

• not a function

• initial value

PART 2: Determine whether a table, graph, or set of points is a function.

• It is a function because every input has only one output.

• It is not a function because the input __ has two outputs __ and __.

Multiple Choice

Does the table represent a function?

• Function

• Not a function

ANSWER:

The table is a function. Every input has only one output.

Multiple Choice

Does the table represent a function?

• Function

• Not a function

ANSWER:

The table is not a function. The input 3 has two outputs -5 and -1.

OR

The table is not a function. The input 2 has two outputs -4 and -2.

Multiple Choice

Does the set of ordered pairs represent a function?

• Function

• Not a function

ANSWER:

This set of ordered pairs is not a function. The input 3 has two outputs 8 and 6.

Multiple Select

Which graphs represent a function? Select all that apply.

ANSWER:

Graphs 1 & 2 are functions because every input has only one output.

PART 3: Identify the constant rate of change and initial value in a table, graph, equation, or written description

• Constant rate of change: slope, m, rise/run, change in y/change in x, "each, every, per"

• Initial value: y-intercept, b, starting amount, when x=0, "start, begin, one-time fee"

Multiple Choice

You rent a car for $200 plus $0.50 per mile driven. What is the initial value?

• 0.50

• 200

• -0.50

• -200

Multiple Choice

You rent a car for $200 plus $0.50 per mile driven. What is the constant rate of change?

• 0.50

• 200

• -0.50

• -200

ANSWER:

You rent a car for $200 plus $0.50 per mile driven.

Constant rate of change = 0.50

Initial value = 200 <-- this is a one-time fee!

Multiple Choice

You are doing a push-up competition for the month of December. You are able to do 3 push-ups at the start of the competition. You increase the number of pushups by 1 every day. What is the initial value?

• 3

• 1

• -3

• -1

Multiple Choice

You are doing a push-up competition for the month of December. You are able to do 3 push-ups at the start of the competition. You increase the number of pushups by 1 every day. What is the constant rate of change?

• 3

• 1

• -3

• -1

ANSWER:

You are doing a push-up competition for the month of December. You are able to do 3 push-ups at the start of the competition. You increase the number of pushups by 1 every day. 

Constant rate of change = 1

Initial value = 3

Multiple Choice

In the equation y=-2x+5, what is the initial value?

• -2

• 5

Multiple Choice

In the equation y=-2x+5, what is the constant rate of change?

• -2

• 5

ANSWER:

In the equation y=mx+b, the constant rate of change is m and the initial value is b.

y=-2x+5

Constant rate of change = -2

Initial value = 5

Fill in the Blanks

What is the initial value in the table?

Fill in the Blanks

What is the constant rate of change in the table?

ANSWER:

• The initial value is 2. Look for when x=0.

• The constant rate of change is 2. Choose two points (rows) in the table. Change in y / change in x = 4/2 = 2.

Fill in the Blanks

What is the initial value of the graph?

ANSWER:

The initial value is the y-intercept or where the line cross the y-axis.

The initial value is -2.

Fill in the Blanks

What is the constant rate of change of the graph?

ANSWER:

The constant rate of change is the slope of the graph. Choose 2 points, count the rise/run, and simplify.

The constant rate of change is 4/6 = 2/3.

PART 4: Compare the constant rate of change or initial value in two functions.

Say which function is greater and explain by stating the number for each function.

Example Answer:

Function A has a greater initial value.

The initial value of Function A is 4 and Function B is -2.

Multiple Choice

Which function has a greater initial value?

• Function A

• Function B

ANSWER:

Function B has a greater initial value. The initial value of Function B is 8 and Function A is 5.

Multiple Choice

Which function has a greater constant rate of change? Explain.

• Function A

• Function B

ANSWER:

Function A has a greater constant rate of change. The constant rate of change for Function A is 3 and Function B is 2.

Studying Tips

• Look over the examples in the digital binder

• Practice the vocabulary on Quizlet or Blooket

• Retry some of the IXLs

• Retry the questions in this Quizizz