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JakeV8 Group TitleBest ResponseYou've already chosen the best response.0
Is this actually a physics or math project or just a question asking for you to solve for the variable "t"?
 one year ago

JakeV8 Group TitleBest ResponseYou've already chosen the best response.0
you can use basic algebra to solve for t by isolating it, but it will be an equation using L. But that might be all you need to do... sort of depends on what the purpose of this question is.
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
just have to solve for t.. i think :/ sorry my computer is lagging!
 one year ago

JakeV8 Group TitleBest ResponseYou've already chosen the best response.0
\[L = \frac{ 980t^{2} }{ 4\pi^{2} }\]
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
yeah, that's it :)
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
here is an example http://www.khanacademy.org/math/algebra/solvinglinearequationsandinequalities/v/solvingforavariable The first step is multiply both sides by 4\(\pi\). Can you do that?
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
The first step is multiply both sides by 4\(\pi^2\). Can you do that?
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
hmm, not really.. :///
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
write \(4 \pi^2\) times on both sides of the equation
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
like i dont understand it because it has the pi? :/ i suck at math
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
pi is just a number if you multiply both sides by 4 pi^2 you get \[ 4 \pi^2 L = 4 \pi^2 \cdot \frac{980 t^2}{4 \pi^2}\]
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
now use a simple rule: if you see something divided by itself , it becomes 1. Does that ring a bell? It makes the right side "simplify"
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
no it doesnt :(
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
ahhh, this is confusing to me
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
Here are some examples \[ 3\cdot \frac{4}{3} = \frac{3\cdot 4}{3}= \frac{\cancel{3}\cdot 4}{\cancel{3}}=4\]
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
do you see anything in your problem that "cancels"?
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
yeah, i get that but it has the pi in the one im doing? :/
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
so the pi would cancel out?:S:/
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
\[ 4 \pi^2 L = \cancel{4 \pi^2} \cdot \frac{980 t^2}{\cancel{4 \pi^2}} \]
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
yeaah, thats what i thought :))
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
it is a good rule to remember. now multiply both sides by \(\frac{1}{980} \)
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
one over what? i can't read that:((
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
first write it down: \[ 4 \pi^2 L \cdot \frac{1}{980}= 980t^2 \cdot \frac{1}{980} \]
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
k 1 sec
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
okays (:
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
the 980's cancel on the right side, right? (that is why we did this) we get \[ t^2 = \frac{4\pi^2 L}{980} \] Do you see how we did that?
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
ohhh, yeah i did
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
the 4 pi^2 L is on the top, and when we multiply fractions, it is top times top and bottom times bottom
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
\[ \frac{4 \pi^2 L}{1} \cdot \frac{1}{980} = \frac{4 \pi^2 L\cdot 1}{1 \cdot 980} = \frac{4 \pi^2 L}{980}\]
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
I would simplify by dividing the top by 4, and the bottom by 4. Can you do that?
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
all of the top?:S i dont know how to simplify because the pi is there? do i use 3.14?:/
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
leave pi alone. if you divide the top by 4 it is doing this \[ \frac{\cancel{4}\pi^2L}{\cancel{4}}\]
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
now divide the bottom by 4: 980/4 is 245 we get \[ t^2= \frac{\pi^2 L}{245} \]
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
do you know how to "solve" for t?
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
multiply both sides by 245?:S
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
im not sureee :(
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
if you multiply both sides by 245 you would get a 245t^2 (making it more "complicated" ) Have you heard of a square root?
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
yeaah i have
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
square roots are how you "undo" squares: \[ \sqrt{x^2}= x\]
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
I would take the square root of both sides
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
can you draw it out for me so i can see what you mean? it makes more sense when you do that:D
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
I've noticed it's easier to do work when someone else is doing it, too. try, it won't hurt
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
it really does help when someone else shows you, but ill draw it on here to see if im right :) im prob not thou ...haha
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
Just draw a big square root over each side
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
dw:1354152167387:dw
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
yes, by the t^2 is inside the root sign. and so is the 245. now use the idea that sqrt(x^2) is x so sqrt(t^2) is ?
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
245? haha.. im not sure :/ or 15? :S
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
no, not a number. square root of x*x is x square root of t*t is t (I guess you have to memorize that) we get \[ t= \sqrt\frac{ \pi^2 L}{245} \]
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
now, you can "simplify" (just to show off how much math you know) use the rule that sqrt(a * b) is the same as sqrt(a) * sqrt(b) so the top is sqrt(pi^2) * sqrt(L) you can simplify sqrt(pi^2) , right?
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
yes?.....
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
use the same rule as for sqrt(x^2) (or sqrt(t^2) for that matter)
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
i dont understand when you say sqrt)x^2) really..
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
we start with \[ t= \sqrt\frac{ \pi^2 L}{245} \] we can "break up" the square root by separating it: \[ t = \frac{ \sqrt{\pi^2}\sqrt{L}}{\sqrt{245}} \] the rule "sqrt(x^2) = x means when you see "something" to the 2nd power inside a square root , you can replace it with just "something" There is a good reason to learn this, but first what is \[ \sqrt{\pi^2} \] ?
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
or, another way to think of it, sqrt undoes the square
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
ooh, that kinda makes more sense. what do you mean what is it?
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
so it would be pi^2?
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
or sqaure root pie? :S
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
or neither? hahaa
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
sqrt(pi^2) is not pi^2 (that would mean sqrt is doing nothing) sqrt(pi^2) is not sqrt(pi) (that would mean pi^2 is the same as pi) sqrt(pi^2) "makes the square go away"
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
if \[ \sqrt{x^2}= x\] and \[ \sqrt{t^2}=t\] what is \[ \sqrt{\pi^2}= ?\]
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
pi..lol
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
yes, so now you have \[ t = \frac{ \sqrt{\pi^2}\sqrt{L}}{\sqrt{245}} \] \[ t = \frac{ \pi\sqrt{L}}{\sqrt{245}} \] finally we can rewrite sqrt(245) as sqrt(5*7*7) or \[ \sqrt{7^2}\cdot \sqrt{5} \] do I dare ask what is sqrt(7*7)?
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
hahah!
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
7*7 = 49 but sqrt(7*7) is 7 (or sqrt(49) is 7) 7*7 is 7^2 and the square root undoes the square.
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
yeaah
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
we now have \[ t = \frac{ \pi\sqrt{L}}{\sqrt{245}} \] \[ t = \frac{ \pi\sqrt{L}}{7\sqrt{5}}
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
\[t = \frac{ \pi\sqrt{L}}{7\sqrt{5}} \]
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
The last step. People (why?) do not like sqrt in the denominator, so we multiply top and bottom by sqrt(5) \[ t = \frac{ \pi\sqrt{L}}{7\sqrt{5}}\cdot \frac{\sqrt{5}}{\sqrt{5}}= \frac{ \pi\sqrt{5L}}{35}\]
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
that is your answer
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
wow, that is a loooot of work!! but thank you so much.. when i reread over it tomorrow, i'll prob be awesome at it ;) haha....ill prob get it! :D are you a teacher?
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
The reason you learn this is to 1. See if you *can* learn it. 2. If you can learn it, it changes how you think (in a good way)
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
I am an engineer for a living..
 one year ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
thats awesome :D
 one year ago
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