Interpreting and Using Exponential Functions

Daniel’s Print Shop purchased a new printer for $35,000. Each year it depreciates (loses value) at a rate of 5%.

Write the equation that represents the situation.

Write the equation using this format with no spaces:

y=a(b)^x

Choose the correct equation for an exponential function that starts at 5 and has a growth factor of 2

Hannah deposits $480 into an account that earns 2.6% annual interest. She makes no further deposits or withdrawals. Which function models the total amount, j(t), in the account after t years?

• j(t) = t(480)^2.6

• j(t) = (480)^2.6t

• j(t) = 1.026(480)^t

• j(t) = 480(1.026)^t

North Dakota has recently had the fastest growing population out of all 50 states. On Jan 1, 2013, the population of North Dakota was 700,000 people. North Dakota’s population has been growing by 5% per year. Express North Dakota’s population, N, in terms of years since 2013, t. Check the BEST answer:

• N=700,000(1.05)t

• N=700,000(1.5)t

• N=700,000(1-0.05)^t

• N=700,000(0.95)^t

Florine-21 has a half-life of 4 seconds. You begin with a 50 mg sample of Florine-21. Which exponential equation would represent the amount of Florine-21after t seconds.

Which of the following equations could represent the image?

• y = 2x +1

• y = 2x²

• y = 2^x

• y = -2^x

Which equation matches the graph

• y = 4^x + 3

• y = 4^x - 3

• y = 4^{x + 3}

• y = 4^{x - 3}

Which equation matches the graph?

• y=2(2)^x

• y=2(1/2)^x

• y=2^x

• y=1/2(2)^x

What is the equation that models this graph?

• y = 2(3)^x

• y = 3(2)^x

• y = 3(½)^x

• y =½(3)^x

Which equation corresponds to the graph below.