SOLUTION: how do i write a quadratic equation from: two people drop rocks from different heights at the same time. the first from 400ft and the second from 160ft.write two functions that des

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Question 596397: how do i write a quadratic equation from: two people drop rocks from different heights at the same time. the first from 400ft and the second from 160ft.write two functions that describe the heights of the rocks.?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
The equations would be:
(1) +h%28t%29+=+-16t%5E2+%2B+400+
and
(2) +h%28t%29+=+-16t%5E2+%2B+160+
+h+ is in feet, +t+ is in seconds
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Notice that for both (1) and (2),
if +t+=+0+ ( just letting of rocks ), then
(1) +h%280%29+=+400+
(2) +h%280%29+=+160+
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You also want to know +h%28t%29+=+0+, which
means the rock has hit the ground.
You don't want +h%28t%29+ to ever be negative,
since the rock would have to burrow into the
ground.
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The equations would be:
(1) +-16t%5E2+%2B+400+=+0+
(1) +-16t%5E2+=+-400+
(1) +t%5E2+=+25+
(1) +t+=+5+
Notice that in 5.1 sec, the stone is still resting
on the ground, and hasn't burrowed into the
ground as the equation would show, ( negative h )
and
(2) +-16t%5E2+%2B+160+=+0+
(2) +-16t%5E2+=+-160+
(2) +t%5E2+=+10+
(2) +t+=+3.162+
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