Asked by alejandro
The mass of a radioactive sample is represented in the graph below. The initial mass of 32 mg decays to 8 mg after 21 hours.
1)What is the half-life of the radioactive sample, in minutes?
2)Solve each equation.
a. 4 8x-1 = 8
b. 3^(2x-5) = 1/27x
1)What is the half-life of the radioactive sample, in minutes?
2)Solve each equation.
a. 4 8x-1 = 8
b. 3^(2x-5) = 1/27x
Answers
Answered by
Steve
8 is 1/4 of 32, so two half-lives = 21 hours.
half-life is 10.5 hours
4^(8x-1) = (2^2)^(8x-1) = 2^(16x-2) = 8 = 2^3
so, 16x-2 = 3
x = 5/16
assuming 1/27x = (1/27)*x,
3^(2x-5) = (3^-3)x
(2x-5)log3 = -3log3 + logx
(2x-2)log3 = logx
nope
assuming a typo, and the x on the right does not belong,
3^(2x-5) = 1/27 = 3^-3, so
2x-5 = -3
x = 1
half-life is 10.5 hours
4^(8x-1) = (2^2)^(8x-1) = 2^(16x-2) = 8 = 2^3
so, 16x-2 = 3
x = 5/16
assuming 1/27x = (1/27)*x,
3^(2x-5) = (3^-3)x
(2x-5)log3 = -3log3 + logx
(2x-2)log3 = logx
nope
assuming a typo, and the x on the right does not belong,
3^(2x-5) = 1/27 = 3^-3, so
2x-5 = -3
x = 1
There are no AI answers yet. The ability to request AI answers is coming soon!
Submit Your Answer
We prioritize human answers over AI answers.
If you are human, and you can answer this question, please submit your answer.