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H=204t-16t^2
Find all the values of t for which the rocket’s height is 100ft

User Pawelropa
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1 Answer

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The values of
\(t\) when the rocket's height is 100 feet, calculated using the quadratic formula, are approximately
\(12.24\) seconds or
\(0.51\) seconds (rounded to the nearest hundredth).

To find the values of
\( t \) when the rocket's height is 100 feet, we'll use the equation given for the rocket's height:


\[ h = 204t - 16t^2 \]

Given that the height
(\( h \)) is 100 feet, set up the equation:


\[ 100 = 204t - 16t^2 \]

Rewrite the equation in standard quadratic form:


\[ 16t^2 - 204t + 100 = 0 \]

Now, to solve for
\( t \) we can use the quadratic formula:


\[ t = (-b \pm √(b^2 - 4ac))/(2a) \]

For the quadratic equation
\(16t^2 - 204t + 100 = 0\), the values of
\(a\),
\(b\), and
\(c\)are:


\[ a = 16, \quad b = -204, \quad c = 100 \]

Now, let's substitute these values into the quadratic formula:


\[ t = (-(-204) \pm √((-204)^2 - 4 \cdot 16 \cdot 100))/(2 \cdot 16) \]

Solving this equation will provide the values of
\( t \) when the rocket's height is 100 feet. Let's calculate it.

Apologies for the confusion earlier. Let's solve the quadratic equation
\(16t^2 - 204t + 100 = 0\) to find the values of \(t\) when the rocket's height is 100 feet.

Using the quadratic formula:


\[ t = (-b \pm √(b^2 - 4ac))/(2a) \]

Given
\(a = 16\),
\(b = -204\), and
\(c = 100\) , let's plug these values into the formula:


\[ t = (-(-204) \pm √((-204)^2 - 4 \cdot 16 \cdot 100))/(2 \cdot 16) \]

Calculating the values:


\[ t = (204 \pm √(41616 - 6400))/(32) \]


\[ t = (204 \pm √(35216))/(32) \]


\[ t = (204 \pm 187.75)/(32) \]

This results in two solutions for
\(t\):


\[ t_1 = (204 + 187.75)/(32) = (391.75)/(32) \approx 12.24 \]


\[ t_2 = (204 - 187.75)/(32) = (16.25)/(32) \approx 0.51 \]

Therefore, when the rocket's height is 100 feet, the values of
\(t\) are approximately
\(12.24\) seconds or
\(0.51\) seconds (rounded to the nearest hundredth).

complete the question

A model rocket is launched with an initial upward velocity of 204 ft/s. The rocket's height h in feet after t seconds is given by the following equation: h = 204t - 16t^2. Find all values of t for which the rocket's height is 100 feet. Round your answer(s) to the nearest hundredth. (If there is more than one answer, use the "or" button.)

User Hing
by
7.6k points