Given the following exponential function, identify whether the change represents growth or decay, and determine the percentage rate of increase or decrease. � = 200 ( 0.98 ) � y=200(0.98) x

Question

delta math 11 grade

Answer 1

Hi Detarrius,

We can write a general form of these kinds of functions, y = A(r)^x

If r > 1, the function is increasing

If r < 0, the function is decreasing. Your function has r = 0.98 so it is decreasing (decay)

In the case where r = 1, then y = A(1)^x, which is just y = A since 1^x is always 1

The percentage rate of decrease depends on r:

for example: when x = 0, y = 200. When x = 1, y = 200*0.98 = 196. If you keep following this for more values, you will see that the value of y decreases by 2% every time we increase x by 1. You can infer this value from r:

1 - r = 0.02

which is 2%