Exercise 42 Page 287

Let's start by recalling the general formula of exponential growth and exponential decay functions. cc Exponential Growth & Exponential Decay [0.8em] y=a(1+r)^t & y=a(1-r)^tIn both cases a and r are positive numbers. For exponential decay r is less than 1. Let's rewrite the given function to match one of the above formulas.

y=5(1.08)^t

WriteSum

Write as a sum

y=5(1+0.08)^t

Our function matches the format of exponential growth. Here a= 5 and r= 0.08. y= 5(1+ 0.08)^t This means that the rate of growth, also known as the percent of change, is 8 %.