Key Features Expon. f(x)'s
Growth or Decay
Growth or Decay
Percent Rate
Word Problems
100
If, y = a(bx), What are the parameters (a & b) and what do they represent?
a = initial amount/y-intercept
b = factor
100
How do I know if an exponential function is exponential decay from an equation?
If the b is in between 0 and 1
100
A bunny population doubles every 6 months. If the starting population is 10, what is the y-intercept of the graph? What is the growth factor?
y-intercept = (0,10)
growth rate = 2
100
What is the percent growth/decay rate?
y=5(0.5)^x
50%
100
2243
200
What is the y-intercept and factor for the function f(x)=2(3)x
y-intercept = 2
factor = 3
200
Find the equation for:
Passes through the points (0, 3.5) and (2, 31.5)
y=3.5(3)x
200
In exponential functions, when b>1 this will cause an exponential growth or decay?
Exponential growth
200
What is the percent growth/decay rate?
y=5(1.3)^x
30%
200
What will be the cost in 17 years?
$32,313.27
300
What is the y-intercept and horizontal asymptote?
y-intercept = (0, 1)
asymptote = y=0
300
f(x)=a(.93)x
Does this functions represent exponential growth or decay? What is the percent growth/decay rate?
Exponential Decay
r = 7%
300
f(x)=37(1.07)x
Does this function represent exponential growth or decay? What's the factor?
Exponential Growth. 1.07.
300
What is the percent growth/decay rate?
y=(0.01)^x
99%
300
16,941 people
400
What's the factor?
b=2
400
Label the following formula:
y = final amount
a = initial amount
r = rate of growth
t = time
400
Does the graph represent exponential growth or decay?
Exponential Growth
400
Is this exponential growth or decay?
What is the percent growth/decay rate?
y=1/2(0.7)^x
Decay. 30%
400
Is the function exponential growth or decay? 
Decay
500
What is the difference between linear functions and Exponential functions
Linear has a constant difference
Exponential has a factor
500
Ms. Wiggins purchased a car for 26,400 and every year it decays by 12%. What can she expect the value of her car to be after 3.5 years?
f(x)=26400(.88)3.5=$16,876.92
500
Annual sales of a fast food restaurant are $530,000 and increasing at a rate of 5%. What will the annual sales be in 6 years?
530,000(1.05)6 =$710,250.69
500
What is the percent growth/decay rate?
y=60(1.33)^x
33%
500
If you put $500.00 into an account and the account earns 3% interest. How much will be in the account after 5 years?
$579.64