Question

Determine whether the function is growth or decay AND its percentage of growth or decay.

y=7(.4)^x

Answer 1

Decay, 60%

Explanation:

Decay because 0.4 < 1

7(.4)¹ = 2.8

%: 2.8/7 × 100 = 40%

Decrease of 60%

Answer 2

decay 60%

Explanation:

y=7(.4)^x

The equation is of the form

y =a b^x

b tells us growth or decay

b>1 growth

b<1 decay

This is decay

To find the percent decay take 1-b

1-.4 = .6

Change this to percent

60%