Question

.

Answer 1

\[t(x)=60(\frac{1}{2})^{\frac{x}{30}}+20\]

Answer 2

initial temp is what you get when t = 0, namely 60 + 20 = 80

Answer 3

god it this slow!!

Answer 4

what merstj said

Answer 5

then set = 28 and solve for t

Answer 6

or rather solve for x

Answer 7

\[T(x)=60(\frac{1}{2})^{\frac{x}{30}}+20\]
\[60(\frac{1}{2})^{\frac{x}{30}}+20=28\]
\[60(\frac{1}{2})^{\frac{x}{30}}=8\]
\[(\frac{1}{2})^{\frac{x}{30}}=\frac{8}{30}=\frac{4}{15}\]

Answer 8

\[\frac{x}{30}=\frac{\ln(\frac{4}{15})}{\ln(\frac{1}{2})}\]

Answer 9

damn is this slow. i think i am done for the night