SOLUTION: The formula D(t)= 6e^-0.1t can be used to find the number of milligrams (mg) D of a certain drug that is in a patient’s bloodstream after t hours, assuming that 6 mg of the drug

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: The formula D(t)= 6e^-0.1t can be used to find the number of milligrams (mg) D of a certain drug that is in a patient’s bloodstream after t hours, assuming that 6 mg of the drug       Log On


   



Question 1149636: The formula D(t)= 6e^-0.1t can be used to find the number of milligrams (mg) D of a certain drug that is in a patient’s bloodstream after t hours, assuming that 6 mg of the drug is administered initially
when t = 0.
When the number of mg of the drug in the patient’s bloodstream reaches 2 mg, the drug
needs to be administered again. Approximately how long until another injection needs to be
administered? You must show this algebraically. You must set up and solve an exponential equation.
Round your final answer to tenths place but do not round until the end.

Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
6e^-0.1t = 2
:
e^-0.1t = 2/6 = 1/3
:
take the natural log of both sides
:
-0.1t = ln(1/3)
:
-0.1t = −1.0986
:
t = −1.0986/-0.1 = 10.986
:
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in approimately 11 hours another injection must be given
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