Exponential Equations

Classify the following graph.

• Exponential Growth

• Exponential Decay

• Logarithmic

What is the asymptote of the parent function y=2^x?

• x=0

• y=0

• x=2

• y=2

James' 70 in. giant peach doubles in size every week. Write an expression that would represent how big the peach is after 5 weeks.

• 70(2)³⁵

• 70(2)⁵

• 2(70)⁵

• 5(70)²

Suppose a culture of bacteria begins with 5000 cells and dies by 30% each year. Write an equation that represents this situation.

• y=5000(0.7)^x

• y=30(5000)^x

• y=5000(1.3)^x

• y=5000x^x

There were 417 cell phones sold at an electronics store in January. Since then, cell phone sales at this store have increased at a rate of 3.75% per month. At this rate of growth, which function can be used to determine the monthly cell phone sales x months after January?

• f(x) = 417(3.75)^x

• f(x) = 417(0.0375)^x

• f(x) = 417(1.0375)^x

• f(x) = 417(1.375)^x

Some banks charge a fee for a savings account that is left inactive for an extended period of time. The equation y = 5000(0.98)^x represents the amount remaining, y, of one account that was left inactive for a period of x years. What does the number 5000 represent in this situation?

• fee charged for an inactive account

• percent of money in the account after x years

• amount of money in the account initially

• amount of money in the account after x years

Does the following equation represent exponential growth or exponential decay? y=105(.80)^x

• Growth

• Decay

For the function f(x) =6(3)^x , what is the y-intercept?

• (6,0)

• (3,0)

• (0,3)

• (0, 6)

Growth or decay?

• Growth

• Decay

What is a, the starting term, for the function: f(x) = 300(1.16)^x?

• 300

• 1.16

• .16

• x