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Algebra Trig word problem. BEST ANSWER 10 points!!!!!!?

The temperature, T(t), in degrees Fahrenheit, during the day can be modeled by the equation

T(t) = -0.7t2 + 9.4t + 59.3,

where t is the number of hours since 6:00 am.

A. At what time is the temperature the highest? (Round to the nearest minute)

- Cant use any calculus and show all work!

2 Answers

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  • Bea
    Lv 5
    9 years ago
    Favorite Answer

    Since it is a quadratic equation with a negative coefficient,

    it is a parabola that opens down.

    The vertex is the maximum.

    The x-coordinate of the vertex is -b/2a.

    Note that t is HOURS.

    t = -b/2a

    t = -(9.4)/2(-0.7)

    t = 9.4/1.4 = 6.71 hours = 6 hours 43 minutes

    6:00 + 6 hrs 43 min ---> 12:43 PM

  • 9 years ago

    Use the quadratic function and use the value you obtain that is not negative (you wouldn't have negative time and you wouldn't have a high negative temperature)

    Source(s): Calculus Student
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