SOLUTION: s=-16t^2+32t+40. How did they get from there calcuating in .5 seconds to -4+16+40? Where did the -4 come in. When I did the problem I got 64+32+40. What I do wrong?
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Quadratic Equations and Parabolas
-> SOLUTION: s=-16t^2+32t+40. How did they get from there calcuating in .5 seconds to -4+16+40? Where did the -4 come in. When I did the problem I got 64+32+40. What I do wrong?
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Question 205116: s=-16t^2+32t+40. How did they get from there calcuating in .5 seconds to -4+16+40? Where did the -4 come in. When I did the problem I got 64+32+40. What I do wrong? Answer by Alan3354(69443) (Show Source):
You can put this solution on YOUR website! s=-16t^2+32t+40. How did they get from there calcuating in .5 seconds to -4+16+40? Where did the -4 come in. When I did the problem I got 64+32+40. What I do wrong?
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-16t^2 at t = 0.5
= -16(0.25)
= -4
