Is it a Function?
x y
2 5
3 6
4 7
5 8
Yes! It is a function.
What is another name for the independent variable?
Input or x
The distance a person walks is a function of time since the walk begins.
Identify the independent and dependent variable from the sentence.
Independent: Time since walk begins
Dependent: Distance a person walks
Function S gives the score in a video game based on the level number. Write the following in function notation: "At level 7, the player has 450 points."
a) S = 450 and 7
b) S(450) = 7
c) S(7) = 450
d) 7(450) = S
Function Q gives a puppy's weight in pounds as a function of its age in months. What does Q(18) represent?
a) the age of the puppy is 18 months
b) the puppy's weight at 18 months
c) the function name is Q
d) 18 pounds
b) Q(18) represents the puppy's weight at 18 months.
x y
2 -2
3 12
4 -4
2 6
No! This is not a function.
What does the dependent variable represent in function notation?
a) f
b) (x)
c) f(x)
f(x)
Input: Time car is parked, hours.
Output: Cost of parking
Describe the function with a sentence of the form "___ is a function of ___"
The cost of parking is a function of the number of hours a car is parked.
Function C gives the temperature in Celsius as a function of time in hours after noon. Which statement is equivalent to : "The temperature was 20 degrees Celsius at 3 hours after noon.
a) C(3)=20
b) C(20)=3
c)3(20)=C
d) C=20+3
a) C(3) = 20
Function T gives the total ticket sales in dollars for a concert based on the number of tickets sold. What does T(500)=12,500 mean?
a) 500 tickets cost $12,500
b) when 500 tickets are sold, the total sales are $12,500
c) 12,500 tickets cost $500
b) T(500)=12,500 means when 500 tickets are sold, the total sales are $12,500
(0,3), (0,4), (2,2), (-4,3), (8,2), (2,6)
No! This is not a function.
Identify the independent variable.
You earn money babysitting. You earn $15 per hour.
Hours spent babysitting is the independent variable.
You buy notebooks for school. Each notebook cost $1.50.
Write a sentence of the form " ___ is a function of ___"
The total cost of the notebooks is a function of the number of notebooks you need/buy
Function Q gives a puppy's weight in pounds as a function of its age in months. Use function notation to represent when the puppy turned a months old, it weighed w pounds.
Q(a)=w
Function H gives the height of a plant in inches as a function of the number of weeks since it was planted. Interpret H(6)=14.
Write a complete sentence explaining what this means.
After 6 weeks, the height of the plant was 14 inches.
Create your own table that is NOT a function AND explain why it is not a function.
answers vary - teacher will check
Identify the dependent variable.
You save money each week. You save $20 each week.
The total amount of money you have saved is the dependent variable.
A phone battery loses a percentage of its charge every hour.
Write a sentence in the form of "___ is a function of ___"
Function P gives the monthly phone bill in dollars as a function of the number of gigabytes used. Write this statement in function notation: "After using g gigabytes, the bill is d dollars.
P(g)=d
Function V gives the value of a car in thousands of dollars as a function of years of ownership. What does V(5) tell you?
After 5 years of ownership, the car is worth v thousand dollars.
Explain in a sentence or two how to determine if a function is a function or not from a table.
answers will vary - teacher will check.
Identify the independent and dependent variable.
A car uses 1 gallon of gas for every 30 miles.
The number of gallons of gas is the independent variable. The number of miles is the dependent variable.
Is the price of a burger a function of the number of patties? Explain your reasoning.
B(Lebron James) = December 30
Function M gives the total cost of a gym membership in dollars as a function of the numbers of months. Look at : M(6)=180.
Person A says "This means 6 dollars per month."
Person B disagrees. What is the correct interpretation of M(6)=180?
This means the 6-month membership cost $180.