Question 407696: lauren dove into a swimming pool from 15 foot high diving board with an initial velocity of 8 per second. Find the time t in seconds it took lauren to enter the water. Use the model for velocity motion given by the equation h=16t^2+vt+s, where h is height in feet , t is seconds, v is the initial upward velocity in feet per second, and s is the initial height in feet.
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! lauren dove into a swimming pool from 15 foot high diving board with an initial velocity of 8 per second.
Find the time t in seconds it took lauren to enter the water.
Use the model for velocity motion given by the equation h=16t^2+vt+s, where
h is height in feet , t is seconds, v is the initial upward velocity in feet
per second, and s is the initial height in feet.
:
I think the equation should be h = -16t^2 + vt + s (-16t^2 is the downward force of gravity)
:
When the diver strikes the water, h = 0, therefore
-16t^2 + 8t + 15 = 0
Multiply by -1 and try to factor this
16t^2 - 8t - 15 = 0
(4t - 5)(4t + 3) = 0
Positive solution
4t = 5
t = 
t = 1.25 seconds to hit the water
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Graphically:
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