Ideas of Functions
What's the Output?
Correlation Types
When will I use this?
Potpourri
100
A relation is function if every input has exactly ______ output(s).
one
100
Use the function rule below to find f(2)
f(x)=10x+9
f(2)=29
100
As x increases, y-increases.
Positive Correlation
100
A phone company charges $40 per month plus $5 per gigabyte of data.
Predict how much 12 gigabytes of data will cost.
$100
Function Rule:
f(x)=5x+40
100
Solve for the variable x:
5x - 4(2x - 3) = 18
x=-2
200
When looking at a graph, what can you use to determine if a graph represents a function?
200
Use the function rule below to find f(2)
f(x)=-2x-5
f(-2)=-9
200
As x increases, y decreases.
Negative Correlation
200
A tomato plant grows 3 inches per week. It starts at 6 inches tall.
Predict after how many weeks the tomato plant will be 21 inches tall.
5 weeks
Function Rule:
f(x)=3x+6
200
Solve for the variable x below:
-4x + 7 ≤ 2x - 5
All numbers greater than or equal to 2
OR
x ≥ 2
300
The domain represents this in a function.
The possible inputs/x-values
300
Use the function rule below to find f(1.5)
f(x)=x-5
f(1.5)=-3.5
300
Type of correlation represented by the following points:
(1,2), (3,5), (7,10), (15,25)
Positive Correlation
300
A candle is 30 cm tall and burns at a rate of 1.2 cm per hour.
Predict the height after 18 hours.
8.4 cm tall
Function Rule:
f(x)=-1.2x+30
300
Solve the system of equations shown below:
y=2x+3
x+4y=39
(3, 9)
400
Why is this set of data points a function?
(1,2), (2,5), (3,7), (5,12)
A relation is a function if every input has exactly one output.
400
Use the function rule below to find f(x+3)
f(x)=2x+5
f(x+3)=2x+11
400
Days of the week and raccoons in your house.
No correlation
400
A water tank begins with 200 liters of liquid and drains at 18 liters per minute.
Predict when the tank will be empty.
Approx. 11 minutes and 6.6 seconds
Function Rule:
f(x)=-18x+200
400
For tickets at a concert, adults cost $12 and children cost $8. Assume that $960 is collected and 90 tickets are sold.
Determine the number of adults and children that attended the concert.
60 adults
and
30 children
500
Why is this set of data points NOT a function?
(1,3), (2,5), (3,7), (4, 9), (5, 11), (5, 13)
A relation is function if every input has exactly one output. Since 5 has an output of 11 and 13, this is NOT a function.
500
Use the function rule below to find f(5x+2)
f(x)=-3x+5
f(5x+2)=-15x-1
500
The miles you drive and the amount of gas left
Negative correlation
500
Big Al has a savings bond of $2,500. Each week, he would rather spend the money on new shoes, costing $44.99 each.
Predict when Big Al's savings bond will run out of money.
Approx. 55 and a half weeks
OR
Approx. 1 year and 3.5 weeks
Function Rule:
f(x)=-44.99x+2500
500
What is the difference between the SLOPES of parallel and perpendicular lines?
Parallel lines have the same slope.
y=2/3x+5
y=2/3x+9
Perpendicular lines have opposite reciprocals.
y=5x-2
y=-1/5x-2