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Veseljchak [2.6K]
3 years ago
14

A small rock falling from the top of a 124-ft-tall building with an initial downward velocity of –30 ft/sec is modeled by the eq

uation h(t) = –16t2 – 30t + 124, where t is the time in seconds. For which interval of time does the rock remain in the air?
t = 2
t > –2
t < 2
t > 2


WHICH ONE?? D:

Mathematics
1 answer:
adelina 88 [10]3 years ago
5 0

Answer:

Third option is correct.

Step-by-step explanation:

The given model is

h(t)=-16t^2-30t+124

Where, h(t) is heigth of rock after time t (in seconds).

The initial height of rock is 124 ft.

The leading coefficient is negative. It means it is a downward parabola.

First we have to the x-intercepts of the function.

0=-16t^2-30t+124

Using quadratic formula, we get

t=\frac{-(-30)\pm \sqrt{(-30)^2-4(124)(-16)}}{2(-16)}

t=-3.8752 and t=2

It means rock remains in the air between -3.875.

The value of t can not be negative, therefore rock remains in the air between 0.

Third option is correct.

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Answer:  The width is:  " 10 in. " .
________________________________________________
Explanation:
________________________________________________
Consider a "rectangular prism".
________________________________________________
The formula for the Volume of a rectangular prism:
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                 in which:
 
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Given the formula:
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Rewrite the formula; by dividing EACH SIDE of the equation by
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