SOLUTION: Solve using the five-step problem-solving process. Show all steps necessary to arrive at your solution. A diver jumps from a 48 foot cliff into the ocean below with an initial v

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Question 251298: Solve using the five-step problem-solving process. Show all steps necessary to arrive at your solution.
A diver jumps from a 48 foot cliff into the ocean below with an initial velocity of 8 ft/sec. The height of the diver from the ocean after t sec is given by h = -16t2 + 8t + 48. When does the diver hit the water?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
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A diver jumps from a 48 foot cliff into the ocean below with an initial velocity of 8 ft/sec. The height of the diver from the ocean after t sec is given by h = -16t2 + 8t + 48. When does the diver hit the water?
:
h = the height at t seconds
:
When it hits the water h = 0, therefore:
-16t^2 + 8t + 48 = 0
Simplify and change the signs, divide by -8
2t^2 - t - 6 = 0
Factor
(2t + 3)(t - 2) =
the positive solution
t = 2 sec
:
Check solution in original equation
h = -16(2^2) + 8(2) + 48
h = -16(4) + 16 + 48
h = -64 + 64
h = 0 when it hits the water
:
:
Swimmer will hit the water in 2 seconds from a height of 48 ft