Evaluating exponential functions
Writing exponential functions
Using exponential functions
Vocabulary
Old stuff
100
Solve the following when x=4
3^x
81
100
When there is percent change, how do you write an exponential function?
1) Change the percent to a decimal
2) Add with 1 (growth) OR subtract with 1 (decay)
100
Solve the following
5^3*5^4
5^7=78125
100
Define equation
A math statement that has an answer
100
Write an equation for the following: a number plus 45 has a total of 200
x+45=200
200
Solve the following when x = 2
91(0.75)^x
51.1875
200
Write an exponential function that shows 23% decay
0.77^x
200
A bank account starts with $400 and earns 2.4% interest every year.
This is an example of...?
Exponential growth
200
Define exponential growth function
A function that grows by multiplying by the same number and increases
200
Write an inequality for the following: Brian can sell cookies and brownies in his bake sale, with a goal of selling at least 120 items.
c+b>=200
300
Evaluate the following when x=0
12^x+4
5
300
DOUBLE POINTS!: Write an exponential function that increases by tripling
3^x
300
There are 45,670 bacteria cells in a Petri dish. After spraying it with disinfectant, the amount of bacteria reduces by 33% every hour. What is the factor?
0.67
300
Define exponential decay function
A function that goes down in value by multiplying by the same number that is less than 1
300
Solve the following equation:
-3x+19=25
x=-2
400
A savings account earns 6% interest each year, compounded 5 times a year. If a person invests $200 and makes no further deposits or withdrawals, what is the balance after 9 years? Evaluate the function
About 342.10
400
A savings account earns 6% interest each year, compounded 5 times a year. If a person invests $200 and makes no further deposits or withdrawals, what is the balance after 9 years? Write the function
200(1+(0.06/5))^45
400
DOUBLE POINTS: What is the formula for compounded interest?
P(1+r/n)^(nt)
400
Define interest
Money charged to someone who borrows money; extra money being charged
400
Solve the following inequality:
81-5x>311
x<-46
500
DOUBLE POINTS!!: The following function shows the cost in dollars of a car, where x is the number of years since 2025. What is the cost in the year 2031?
73000(0.92)^x
About 44263.92
500
When his nephew turns 18, Mr. Reyes wants to open a savings account with $3000. It can earn interest in the following ways:
a. Growing by 9.5% each year
b. Growing by $500 each year
Write the functions for both options showing how much money Mr. Reyes' nephew will have when he turns 30
A=3000*1.095^12
B=3000+500(12)
500
Calculate f(5) / f(2)
216
500
Define additional
More; using addition
500
A lemonade stand sells cans of lemonade for $2 each and bottles of water for $1.50 each. They need to raise at least $500 and can accept a maximum of 360 cans and bottles combined. Create a system of inequalities to model this scenario
{(2x,+,1.50y,>=,500),(x,+,y,<=,360):}