Question

How do I find how much time in minutes there is for the internal temperature of 30 degrees for this equation: T(t) = 63(0.5)t/10 + 19

Answer 1

Set T(t)=30

Answer 2

\[T(t) = 63(0.5)^{t/10}+19\]

Answer 3

yes I got that

Answer 4

but then what?

Answer 5

\[11=31.5^{t/10}\]

Answer 6

almost \[11=63(.5)^{\frac{t}{10}}\] divide by 63

Answer 7

why do I divide by 63? o.O

Answer 8

i don't get it 'cause why is the answer 25 min?

Answer 9

Because you want to make the "t" in the power be by itself, this is one way of going about it.Getting rid of everything around one step at a time.

Answer 10

can you show me? please?

Answer 11

11/63. That's not your final answer.

Answer 12

okay I got that.

Answer 13

after that take Logarithm to the base (1/2), i know it's odd but that's what it is, and then multiply by 10.

Answer 14

logarithm? how?

Answer 15

I got to go, but go to the link and click on "Show Steps" on the very second box you see http://www.wolframalpha.com/input/?i=Solve%5B30%3D63%28.5%29%5E%28t%2F10%29%2B19%2Ct%5D

Answer 16

thank you!