Question

Determine if the equation y = 2(0.4)x represents exponential growth or decay.

Answer 1

Te way you wrote your equation is confusing & as it is cannot be an exponential function unless it is written as follows:

either y = 2^(0.4)x or y=2^(0.4)^x

In the first case it's growing as x grow
in the second case is decaying as x is growing.

Answer 2

In this format, we can either use latex or enter a "^" to show that we are raising something to a power....

y=2(0.4)^x

This is exponential decay because the rate is less than 1, in this case 0.4.

All exponential functions can be expressed as:

F=Ir^t, F=final amount, I=initial amount, r=rate, t=time