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3 years ago

7

The formula S=16t^2 is used to approximate the distance S, in feet, that an object falls freely from rest in t seconds. The heig

ht of a building is 1221 feet . How long would it take for an object to fall from the top

2 answers:

astraxan [27]3 years ago

7 0

H(t)=-16t^2+1221 is the function for the height as a function of time. It will hit the ground when h=0 so:

-16t^2+1221=0

16t^2-1221=0

16t^2=1221

t^2=1221/16

t=√(1221/16) seconds

t≈8.74 seconds (to nearest hundredth of a second)

FinnZ [79.3K]3 years ago

4 0

S=16t^2
1221=16t^2
1221/16=t^2
square root of 76.3=t
t=8.7

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