How do you determine if the equation $y= 0.5 (0.9)^x$ represents exponential growth or decay?

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Answer 1 · 2017-10-30T20:04:38

Anything to the $x$ will be growth, if it's $n^(color(red)-x)$ then it'll be decay.

$n^(-x) = 1/n^x$

Therefore as $x$ increases, $y$ will decrease.

When you have $n^x$ as $x$ increases so will $y$ .

How do you determine if the equation y= 0.5 (0.9)^xy= 0.5 (0.9)^x represents exponential growth or decay?