Vocabulary
Evaluating Functions
Solving for x
Is it a Function?
100
What is the definition of domain?
A set of input values (all values of x).
100
Evaluate f(2) if f(x)=-3x
f(2) = -6
100
Find the value of x when f(x) = 12:
f(x) = 2x+6
x = 3
100
Is it a function? {(2, 3), (4, 5), ( -2, 6)}
Yes, each input has exactly one output.
200
What is the definition of range?
The set of output values (all values of y).
200
Evaluate f(7) if f(x)= -(4x+2)
f(7) = -30
200
Find the value of x when f(x) = 12:
f(x) = -2x+6
x = -3
200
Not a function
300
What describes a function?
a) An input and output relationship
b) An independent and dependent variable relationship
c) For every domain value, there is one range value to go with it
d) all of the above
All of the above!
300
Evaluate f(-6) if f(x)=x - 9
f(-6) = -15
300
Find the value of x when f(x) = 12:
f(x) = -2x-6
x = -9
300
Is it a function? Justify your answer.
| x | y |
| 2 | 4 |
| 1 | 5 |
| 2 | 6 |
No, the input of 2 has two different outputs.
400
Sort the following terms into two groups:
Independent variable
Dependent variable
y-value
x-value
input
output
{independent variable, x-value, input}
{dependent variable, y-value, output}
400
Evaluate f(4) if f(x)=25 - 4x
f(4) = 9
400
Keith is driving from Orlando to Tampa for a disc golf competition. He has 145 miles to drive and is traveling at 45mph.
The function f(x) = 145 - 45x represents the distance f(x) Keith has left to drive after x hours of driving. After 3 hours, how much farther does Keith have to drive?
f(3) = 145 - 45(3)
f(3) = 10
Keith has 10 miles to go
400
Is it a function? Justify your answer.
Yes, it passes the Vertical Line Test.
500
Is the following situation classified as discrete or continuous?
The temperature is slowly rising in a classroom where the air conditioning has gone out. It started at 72-degrees and now it's 80-degrees!
Continuous, because temperature doesn't rise 1-degree at a time. Decimal values for temperature exist.
500
Evaluate f(3) if f(x)=3(x + 5) - 2
f(3) = 22
500
Jeremy is buying a lot of disc golf frisbees. The function f(x) = 15x + 5 represents the cost f(x) of buying x frisbees.
How much will it cost Jeremy if he wants to buy 10 frisbees?
f(10) = 15(10) + 5
f(10) = 150 + 5
f(10) = $155
500
Function!
It's ok that the 4 and 2 both point to 9.