Answers:
Problem 7) Decay
Problem 8) Growth
Problem 9) Growth
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Explanation:
The base of the exponent will tell us if we have growth or decay.
In general, we have an equation in the form y = a*b^x with b as the base of the exponent
We can have b = 1+r where r is the growth rate. If r is negative, then that growth is really decay (or the amount is shrinking)
For problem 7, the base is 0.04 so 1+r = 0.04 leads to r = -0.96; so the amount is shrinking or decaying by 96% each time x increases by 1.
In problem 8, we have growth because 1.4 = 1+0.40 = 1+r so r = 0.40 = 40% growth
Finally, in problem 9, we can break up the base 6 into 6 = 1+5.0 = 1+r meaning r = 5.0 = 500% growth
