The temperature at a state park for one day in June can be approximated by the function T(x) = 0.264x2 - 4.752x + 81 0 ≤ x ≤ 18
where T is degrees Fahrenheit and x is the number of hours after 5 PM on Friday. What was the lowest temperature reached? Round to the nearest whole degree.
2 answers:
Answer:
60 °F
Step-by-step explanation:
The function can be put into vertex form:
T(x) = 0.264(x² -18x) +81 . . . . factor the leading coefficient from 1st 2 terms
Now, we add the square of half the x-coefficient inside parentheses and subtract the same quantity outside parentheses.
T(x) = 0.264(x² -18x +81) +81 -0.264·81
T(x) = 0.264(x -9)² +59.616
The low temperature for the day was approximately 59.6 °F, which rounds to 60 °F.
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