Download Name Date Class Understanding Relations and Functions Practice

Name _______________________________________ Date __________________ Class __________________
LESSON
3-2
Understanding Relations and Functions
Practice and Problem Solving: C
Graph each relation. Then explain whether it is a function or not.
1. {(1, 2), (2, 2), (3, 3), (4, 3)}
2. {(1, 5), (2, 4), (3, 5), (3, 4), (4, 4), (5, 5)}
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Solve.
3. Locate 5 points on the first graph so that it shows a function. Then change
one number in one of the ordered pairs. Locate the new set of points on the
second graph to show a relation that is not a function. Explain your strategy.
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4. Identify whether the graph shows a function or a relation that is not a
function. Explain your reasoning.
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5. The function INT(x) is used in spreadsheet programs. INT(x) takes any
x and rounds it down to the nearest integer. Find INT(x) for
x  4.6, 2.3, and 2. Then find the domain and range.
Original content Copyright © by Houghton Mifflin Harcourt. Additions and changes to the original content are the responsibility of the instructor.
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Name _______________________________________ Date __________________ Class __________________
LESSON 3-2
Practice and Problem Solving C
1. It is a function because each input has exactly one output.
2. It is not a function because 3 is paired with two different outputs.
3. Sample answer
Sample explanation I know that a domain value cannot have two different range values, so I
changed one domain value to match another domain number. This means one domain
member has two range values.
4. The first graph is not a function because a vertical line passes through the curve more
than one time. The second graph is a function because a vertical line only passes
through the curve once.
5. INT(4.6)  4, INT(2.3), INT(SQRT{2})  1
Domain and range in general for INT(x)
D  All real numbers, R  All integers
Domain and range for INT(x) for given values of x: D  {4.6, 2.3, SQRT{2}},
R  {3, 1, 4}
solution $66
Practice and Problem Solving C
1. D {2, 5, 7, 8}; Sample answer I substituted each value of the range in the function for
f(x) and worked backward to solve the equation to find the value of x.
Original content Copyright © by Houghton Mifflin Harcourt. Additions and changes to the original content are the responsibility of the instructor.
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