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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"?
 2 years 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.
 2 years 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!
 2 years ago

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

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

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

phi Group TitleBest ResponseYou've already chosen the best response.1
write \(4 \pi^2\) times on both sides of the equation
 2 years 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
 2 years 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 \[ 4 \pi^2 L = 4 \pi^2 \cdot \frac{980 t^2}{4 \pi^2}\]
 2 years 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"
 2 years ago

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

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

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

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

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

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

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

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

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

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

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

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
okays (:
 2 years 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?
 2 years ago

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

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

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

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

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

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
im not sureee :(
 2 years 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?
 2 years ago

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

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

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

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

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
dw:1354152167387:dw
 2 years 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 ?
 2 years ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
245? haha.. im not sure :/ or 15? :S
 2 years 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 \[ t= \sqrt\frac{ \pi^2 L}{245} \]
 2 years 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?
 2 years ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
yes?.....
 2 years 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)
 2 years ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
i dont understand when you say sqrt)x^2) really..
 2 years 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 \[ \sqrt{\pi^2} \] ?
 2 years ago

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

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

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

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
or neither? hahaa
 2 years 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"
 2 years ago

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

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
pi..lol
 2 years 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)?
 2 years ago

heathernelly Group TitleBest ResponseYou've already chosen the best response.1
hahah!
 2 years 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.
 2 years 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}}
 2 years ago

phi Group TitleBest ResponseYou've already chosen the best response.1
\[t = \frac{ \pi\sqrt{L}}{7\sqrt{5}} \]
 2 years 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) \[ t = \frac{ \pi\sqrt{L}}{7\sqrt{5}}\cdot \frac{\sqrt{5}}{\sqrt{5}}= \frac{ \pi\sqrt{5L}}{35}\]
 2 years ago

phi Group TitleBest ResponseYou've already chosen the best response.1
that is your answer
 2 years 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?
 2 years 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)
 2 years ago

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

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