Question 118401: Please assist me with this question. Iam taking beginning algebra online and the book does not give a example of hoe to answer word problems.
If an object is given an initial velocity of v0 feet per second from a height of S0 feet, then its height S after t seconds is given by the formula . A rock is thrown into the air at 26 feet per second from a height of 13 feet. How long does it take to reach the earth?
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! If an object is given an initial velocity of v0 feet per second from a height of S0 feet, then its height S after t seconds is given by the formula . A rock is thrown into the air at 26 feet per second from a height of 13 feet. How long does it take to reach the earth?
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h(t) = -16t^2+vot+so
Your Problem:
h(t) = -16t^2+26t+13
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h(t) will be zero when the object reaches the ground.
You need to solve h(t)=0
-16t^2+26t+13 = 0
Use the quadratic formula to solve for "t":
t = [-26 +- sqrt(26^2-4*-16*13)/(-32)
t = [-26 +- sqrt(1508)]/-32
Positive answer:
t = [-26-38.833]/-32
t = [-64.8330]/(-32)
t = 2.026 seconds
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Cheers,
Stan H.
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