Question

Identify the following as growth or decay. Explain your reasoning

Answer 1

We have a exponential model expressed as:

`y=3.05\cdot(0.87)^x`

We have to identify if this model as a exponential growth or exponential decay by looking at the base of the exponent x:

• if it is smaller than 1, the model is an exponential decay.

,

• if it is greater than 1, the model is an exponential growth.

In this case, the base is 0.87, which is smaller than 1, so it is an exponential decay. We can see that increasing values of x result in decreasing values of y:

Answer: the model is an exponential decay.