SOLUTION: A person standing close to the edge on the top of a 160-foot building throws a baseball vertically upward. The quadratic function, s(t)= -16t^2+64t+160 models the ball’s height w
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-> SOLUTION: A person standing close to the edge on the top of a 160-foot building throws a baseball vertically upward. The quadratic function, s(t)= -16t^2+64t+160 models the ball’s height w
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Question 1146084: A person standing close to the edge on the top of a 160-foot building throws a baseball vertically upward. The quadratic function, s(t)= -16t^2+64t+160 models the ball’s height where s(t) is the height and t is the number of seconds after the ball is thrown.
(Note that s(t) is just function notation for the height of the ball and NOT s
multiplied by t; also note where the initial height and initial velocity values play a role in the equation.
The ball will never reach a height of 300 ft. How can this be determined
algebraically? Show the algebra here Found 2 solutions by ikleyn, richwmiller:Answer by ikleyn(52778) (Show Source):
Try to solve the equation
= 300.
It is equivalent to
= 0.
Calculate its discriminant d = = -4864.
The discriminant is a negative real number -- hence, the original equation HAS NO real solutions.
It is the answer to the problem's question.
There are other ways to answer this question, too.
But this one is a quickest.
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These words "close to the edge" were introduced into the problem formulation with the only goal to confuse the reader.
It is "pure US american" style formulating Math problems (to load them with excessive and unnecessary words).
In normal mathematical formulation, a professional and knowledgeable author never uses such tricks.
My advise to the author is to remove these words from the text.
You can put this solution on YOUR website! Tutor ikleyn and others
A big part of solving problems in the real world is to know what is needed and what is not needed to solve a problem.
Your dislike of such "trick" questions is pure academic snobbery.
If you don't like such problems then avoid them.
Stick to solving problems that suit you.
BTW I don't admit that it is "pure US american" style. The style of having extraneous info is valid for teaching real world problems.
