SOLUTION: Please help me solve this word problem: A disc is thrown into the air and follows a path modeled by the function h(t)=7.8+22t-5t^2, where time, t, is in seconds and height h(t) is
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-> SOLUTION: Please help me solve this word problem: A disc is thrown into the air and follows a path modeled by the function h(t)=7.8+22t-5t^2, where time, t, is in seconds and height h(t) is
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Question 882146: Please help me solve this word problem: A disc is thrown into the air and follows a path modeled by the function h(t)=7.8+22t-5t^2, where time, t, is in seconds and height h(t) is in meters. Determine when the ball will land to the nearest hundredth. Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website! The equation is a parabola
The ball is released at
and
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You want to know what is
when for the 2nd time
( the ball comes back to earth )
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This is the same as finding both of
the roots of the equation
Set and use the
quadratic formula to find roots
----------------------------
The ball lands in 4.73 sec
Note that I chose the largest positive root as the
correct one for when the ball will land
Here's the plot: at looks pretty close to