If 6r + 7 = 13 + 7r, then what is the value of 4r ?
2 answers:
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Slope of a Line Passing through two points (x₁ , y₁) and (x₂ , y₂) is given by :
Given Points are (-3 , 5) and (6 , -1)
here x₁ = -3 and x₂ = 6 and y₁ = 5 and y₂ = -1
Option D is the Answer
Answer:
(b) 67
Step-by-step explanation:
A solution to the differential equation describing the temperature according to Newton's Law of Cooling could be written as ...
T = (final temp) + (initial difference)×(decay factor)^t
where the decay factor is the fraction of change during 1 unit of time period t.
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Here, the initial difference of 100-25 = 75 degrees decays to 90-25 = 65 degrees in 1 minute. So, the units of t are minutes, the decay factor is 65/75, the initial difference is 75 degrees, and the final temperature is 25 degrees. That lets us write the equation as ...
T = 25 +75(65/75)^t
Then for t=4, the temperature is ...
T = 25 +75(13/15)^4 ≈ 67.3 . . . . degrees
After 4 minutes the temperature of the coffee is about 67 degrees.
