h(t) = -9.8t2 – 10t + 330, where t is in seconds, and height is in meters. After how many seconds will the stone hit the ground?
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You want to solve
-9.8t^2 - 10t + 330 = 0
Use the quadradic formula
`t = (-b+-sqrt(b^2-4ac))/(2a)`
t = 6.335 sec or -5.315 sec.
Obviously time is only positive so the answer is 6.335 seconds
well the stone hits the ground when the height = 0
And here you have given a height function
so we only need to set it equal to zero.
Using quadratic formula ((-b+/-sqrt(b^2-4ac))/2a
plugging in all the numbers
a= -9.8 b- -10 c= 330
the answer is 6.335 or -5.315 and the unit is seconds.
Since time really couldn't be negative, (time machine?)
the only legitmate answer to this question is 6.335 seconds
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