Is there a simpler way to solve for time in this algebraic equation?

  • Thread starter Thread starter jKotha
  • Start date Start date
  • Tags Tags
    Algebra Stuck
Join the discussion
Registration is free. Start your own thread to ask a follow-up.
3 replies · 2K views
jKotha
Messages
30
Reaction score
0
hey hey.. I need help again. I can't believe I've forgotten my simple algebra. Anyway.. is there a way to solve the following without using the quadratic equation?

0 = (22)t + 1/2(-9.8)t^2

I'm tryin to isolate t, so i can solve for time. I know you can factor it out as follows..

0 = [22 + 1/2(-9.8)t]t

Thats where I am stuck... how do i get this in the form.. t = xxxxx

Thanks for the help..
 
Physics news on Phys.org
[tex]22t -4.9t^{2} = 0 \rightarrow t(22-4.9t) = 0[/tex]

[tex]t = 0[/tex] or [tex]22-4.9t = 0, t = 4.49[/tex]
 
where did the 4.9 come from? nevermind.. figured that out.. THANKS!>. i feel really dumb now because i should have known that.. sometimes i complicate myself too much.
 
Last edited:
Thats usually the best method but for this one it is not necessary.
Picking up from u
0 = [22 + 1/2(-9.8)t]t
Therefore
t = 0 and 22 + 1/2 (-9.8)t =0
finally:
t= 0, 4.49s

I think it is the second answer that you probably want. Since this type of question is probably asking when the onject will return to its original position.