A catapult launches a boulder with an upward velocity of 122 feet per second. The height of the boulder H in feet in after T seconds is given by the function H(t)= -16t^2 + 122t + 10. what is the boulders maximum height. how long does it take the boulder to reach it's maximum height

Question

mathstudent55 · Answer

At the moment of launch, t = 0, what height is the boulder at?

anonymous · Answer

0 I think

mathstudent55 · Answer

Don't guess. Just plug in t = 0 in the equation.
What do you get for h?

anonymous · Answer

i have no idea that's why im here asking for help

mathstudent55 · Answer

You are given the equation

$h(t) = -16t^2 + 122t + 10$

which represents the height, h, of the boulder at time, t.
Right?

anonymous · Answer

yes but when i add them together i get 116 and that is not right

anonymous · Answer

how or what do i need to do to get the right answer im not asking for the answer im asking how to get the answer

mathstudent55 · Answer

You don't add anything together yet.

Since we know the height as a function of time, we are going to find the height when the boulder is launched. At the very moment of the launch of the boulder, time is zero, t = 0.

At t = 0,

$h(t) = -16t^2 + 122t + 10 $

$h(0) = -16(0^2) + 122(0) + 10 $

$h(0) = 10$

This means the boulder is at a height of 10 ft when it is launched.

anonymous · Answer

Would it be 242.56 feet after 3.81 seconds

mathstudent55 · Answer

I don't know. I haven't solved the problem yet, and I have no answers to choose from.

mathstudent55 · Answer

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