Answer:
7 seconds
Step-by-step explanation:
Ballistic motion is usually modeled in the vertical direction in US customary units by the equation h(t) = -16t^2 +v0·t +h0, where v0 and h0 are the initial velocity and height, and h(t) is the height as a function of time in seconds. For the given initial conditions, the equation of vertical motion will be ...
h(t) = -16t^2 +64t +336
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This question asks you for the value of t for which h(t) = 0. We can solve that equation by factoring.
0 = -16t^2 +64t +336
0 = t^2 -4t -21 . . . . . . . . divide by -16
0 = (t -7)(t +3) . . . . . . . factor the quadratic
t = 7 . . . . . . the positive value of t that makes the equation true
The ball will return to the ground after 7 seconds.
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<em>Additional comment</em>
A graph of the function reveals the ball reaches a maximum height of 400 feet after 2 seconds.
In metric units, the equation is h(t) = -4.9t^2 +v0·t +h0, where distances are in meters instead of feet. Time is still in seconds.
The answer to this is A. 650. You find the surface area of the two cubes, then the rectangular prism, then you add them together.<span />
I don’t know the answer but I recommend using photomath