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Emily778
Group Title
check for extraneous solutions.
sqrt x+7x=1
Please show step by step on how to do this. Thankyou.
 10 months ago
 10 months ago
Emily778 Group Title
check for extraneous solutions. sqrt x+7x=1 Please show step by step on how to do this. Thankyou.
 10 months ago
 10 months ago

This Question is Closed

RolyPoly Group TitleBest ResponseYou've already chosen the best response.0
Let \(u=\sqrt{x}\), then x = \(u^2\) Now, the equation becomes \[u+7u^2=1\] Can you do it?
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
@Krazete
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
I don't get the way you're explaining it to me @RolyPoly
 10 months ago

Krazete Group TitleBest ResponseYou've already chosen the best response.0
Please make use of parentheses. The way you write problems is sorta confusing. Is it √(x+7)x=1 or ...?
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
I guess. Sorry, it doesn't show parentheses on my math problem.
 10 months ago

RolyPoly Group TitleBest ResponseYou've already chosen the best response.0
Is the equation (1)\(\sqrt{ x+7x} =1\) or (2) \(\sqrt{x}+7x=1\)?
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
nvm, i got the answer. Thx
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
nvm.. I tried wolframalpha. But only get two step by steps each day:(
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
I'll have to get the answer tomorrow.
 10 months ago

RolyPoly Group TitleBest ResponseYou've already chosen the best response.0
It would be better if you know how to solve it, instead of just relying on WolframAlpha.
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
eh, true. But lets be honest with ourselves, I'm never going to use this advanced of math in the future.
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
Honestly, I just need credits/passed classes
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
you can argue all you want, but it's true.
 10 months ago

RolyPoly Group TitleBest ResponseYou've already chosen the best response.0
Don't want to argue, just want to help you pass the course and you can learn how to solve it at the same time :)
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
can you just show me please? I'm 18 lessons behind:(
 10 months ago

nikato Group TitleBest ResponseYou've already chosen the best response.2
\[\sqrt{x+7}x=1\]
 10 months ago

nikato Group TitleBest ResponseYou've already chosen the best response.2
add x to both sides
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
It would be a different story if I wasn't that behind
 10 months ago

RolyPoly Group TitleBest ResponseYou've already chosen the best response.0
\[\sqrt{x7x}=1\]\[\sqrt{x7}x=1\]\[\sqrt{x}7x=1\] Which one is your question?
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
like this @nikato dw:1388896983931:dw
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
the 2nd one @RolyPoly
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
what next?
 10 months ago

nikato Group TitleBest ResponseYou've already chosen the best response.2
so now u havedw:1388897108757:dw now square both sides
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
i know 9 is the solution
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
what next?
 10 months ago

nikato Group TitleBest ResponseYou've already chosen the best response.2
did u square both sides. and simplified it?
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
how do I simplify it?
 10 months ago

nikato Group TitleBest ResponseYou've already chosen the best response.2
dw:1388897450469:dwdoes that make sense?
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
what next?
 10 months ago

nikato Group TitleBest ResponseYou've already chosen the best response.2
subtract x and 7 on both sides so that the equation equal 0
 10 months ago

nikato Group TitleBest ResponseYou've already chosen the best response.2
dw:1388897691356:dw
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
what next? :D ha
 10 months ago

nikato Group TitleBest ResponseYou've already chosen the best response.2
dw:1388897800670:dw can u factor the right side?
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
can you show me? eheh
 10 months ago

nikato Group TitleBest ResponseYou've already chosen the best response.2
dw:1388898386363:dw
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
it has to be 9.
 10 months ago

nikato Group TitleBest ResponseYou've already chosen the best response.2
no, i dont think 9 is a solution. try pluggin it back into the origianl equation. it doesnt work
 10 months ago

nikato Group TitleBest ResponseYou've already chosen the best response.2
dw:1388899069611:dw
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
then you did it wrong. Ugh. Wolfram said it was 9
 10 months ago

nikato Group TitleBest ResponseYou've already chosen the best response.2
no, im for sure 9 is not an answer. it doesnt make sense. its one fo those^
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
@Krazete is he wrong or not?
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
sorry, nikato. I gotta make sure.
 10 months ago

nikato Group TitleBest ResponseYou've already chosen the best response.2
yea, its fine. whatever u feel is right
 10 months ago

Krazete Group TitleBest ResponseYou've already chosen the best response.0
nikato's right.
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
okayy,, it's just wolfram said the solution was 9. But I guess it's better to have something than nothing at all.
 10 months ago

nikato Group TitleBest ResponseYou've already chosen the best response.2
maybe u typed in the wrong equation in wolfrma
 10 months ago

Krazete Group TitleBest ResponseYou've already chosen the best response.0
Look at what Wolfram says under "input." Is it the same as your problem? It might've calculated √x instead of √(x+7). Parentheses are quite important.
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
nikato, what do I do next? Sorry for doubting you
 10 months ago

nikato Group TitleBest ResponseYou've already chosen the best response.2
dw:1388899779946:dw solve for x. did most of the work. should be easy for u. there are suppose to be 2 answers
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
one of them is 2.
 10 months ago

nikato Group TitleBest ResponseYou've already chosen the best response.2
yes. and the other?
 10 months ago

nikato Group TitleBest ResponseYou've already chosen the best response.2
no, 3. so now u want to find if there is anyextraneous answers
 10 months ago

nikato Group TitleBest ResponseYou've already chosen the best response.2
plug both back into the equation and see if they make sensedw:1388900195738:dw
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
ugh. How much more is there??
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
what next?
 10 months ago

nikato Group TitleBest ResponseYou've already chosen the best response.2
no, this is it. check if both of those equation are true. if they are not, then that "x" is extraneous
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
thanks. :p
 10 months ago

nikato Group TitleBest ResponseYou've already chosen the best response.2
WAIT NO. its either 2 or 3. i helped plug in both in for x the first one is x=2 and the other is x=3
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
I did it in my calculator. How'd you get your answer?
 10 months ago

nikato Group TitleBest ResponseYou've already chosen the best response.2
no, thats not what i meant
 10 months ago

nikato Group TitleBest ResponseYou've already chosen the best response.2
dw:1388901004098:dw
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
I'm sorry, I still don't get how you got those answers. I got 5 and 1. 1 was correct. 5 was incorrect.
 10 months ago

nikato Group TitleBest ResponseYou've already chosen the best response.2
yes. so that means 3 is the extraneous answer. remember how we worked the problem, and got 2 and 3 as the naswer. however when u plug 3 back into the original equation u get 5 instead of 1. which means the answer doesnt "work" which we call an extraneous answer
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
so what is the answer???
 10 months ago

nikato Group TitleBest ResponseYou've already chosen the best response.2
becuz like i said ^ 3 is an extraneous solution
 10 months ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.0
so, I would put "x=2 only"?
 10 months ago
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