The answer would be 18 minutes.
15/9 = 30/x
cross multiply
15x=270
then divide
x=18
Answer:
45.50° F
Step-by-step explanation:
As per Newton's law,

When T(t) is the final temperature
= Temperature of surrounding
= Initial temperature
t =duration of cooling
k = constant


Now take natural log on both the sides



4.6347 - 5.0434 = -5k

k = 0.0817

= 
= 155 (02935)
= 45.49 ≈ 45.50° F
You have to add 4 and 9 then drop your variable
Answer:
y = -4/3 x - 1/3
Step-by-step explanation:
y = -4/3 x + b
5 = -4/3 (-4) + b
15 = 16 + 3b
b = -1/3
y = -4/3 x - 1/3
29-4 = 25
29+4 = 33
So, from 25 to 33 minutes.