It's important that you use the correct symbol to indicate exponentiation.
<span>f(x) = 0.4(3)x f(x) = 3(0.5)x f(x) = 0.8(0.9)x f(x) = 0.9(5)−x should be written as:
</span><span>f(x) = 0.4(3)^x f(x) = 3(0.5)^x f(x) = 0.8(0.9)^x f(x) = 0.9(5)−x.
Please double-check that last problem, as I am unsure of whether you meant 0.9^5 or (0.9)(5).
f(x) = 0.4(3)^x is definitely an exponential function.
Please try again. Do those problems that you can do an ask questions about the others.
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Answer:
A. T = 20°C - (2.8°C/h × 4h)
Step-by-step explanation:
The rate of change of temperature (-2.8°C/h) is multiplied by time (4h) to get the change in temperature (-11.2°C). That change is added to the initial temperature (20°C) to find the temperature after 4 hours.
Only equation A properly expresses this calculation.
In choice B, the rate of change is (wrongly) shown as +2.8°C/h. In the other choices, the combinations of units are nonsense. (What is a °C·h?)
Answer:
11
Step-by-step explanation: