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Emily778
Group Title
Solve the quadratic equation by completing the square.
x^212x+7=0
 one year ago
 one year ago
Emily778 Group Title
Solve the quadratic equation by completing the square. x^212x+7=0
 one year ago
 one year ago

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SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
add 29 to both sides.
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
can you add 29 to both sides?
 one year ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.1
which sides?
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
Both. \[x^212+7+29=0+29\]
 one year ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.1
and why 29?
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
To make the left side into perfect square because you have to have (6) (6) which equals 36.
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
x^2  12x + 7 = 0 x^2  12x = 7 x^2  12x + (12/2)^2 = (12/2)^2  7 x^2  12x + 36 = 36  7 (x  6)^2 = 29 Take square root of both sides to finish solving for x
 one year ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.1
Oh. Okay. I still don't quite get it, but lets move on. What shall I do next? :D
 one year ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.1
Uhh... which one is right?
 one year ago

gorv Group TitleBest ResponseYou've already chosen the best response.2
x^22*x*6+7=0 x^22*x*6+3636+7=0 (x^22*x*6+36)29=0 (x6)^229=0 (x6)^2=29 x6=29^1/2 x=(29)^1/2+6
 one year ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.1
Are all of these right, just in different ways?
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
You add 36 to both sides, not 29
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
But 36  7 = 29
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
@Hero, no you add 29, because that makes the left side into perfect square. @Emily778, I know what you are confused about, lets learn how to complete the square.
 one year ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.1
I'll just do this x^2  12x + 7 = 0 x^2  12x = 7 x^2  12x + (12/2)^2 = (12/2)^2  7 x^2  12x + 36 = 36  7 (x  6)^2 = 29
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
@SolomanZelman, if that's true, then explain how I got my result
 one year ago

gorv Group TitleBest ResponseYou've already chosen the best response.2
actually in (a+b)^2=a^2+b^2+2ab here 2ab is 12x=2*x*6 so u need to make b^2 that is 36
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
I know exactly how the process works and what to add to both sides.
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
@Emily778, do you get how I came up with 29? lets do a different example. GUYS PLEASE, LETS TEACH HER, NOT DO HER WORK> She needs to understand.
 one year ago

gorv Group TitleBest ResponseYou've already chosen the best response.2
@hero if u will add 29 both side than on x^212x+7+29=29 x^212x+36=29
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
She'll only understand if those teaching know what they are talking about
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
STOP ARGUING!
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
YES, add 29
 one year ago

gorv Group TitleBest ResponseYou've already chosen the best response.2
@hero plzz plzzzz plzzzz for god sake use little of ur mind
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
@Emily778, do you get how I came up with 29? Do you want to learn how to complete the square?
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
I think @Emily778 already has it figured out lol
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
MODERATOR, please don't ruin the thread, and confuse teh asker, lets teach her!
 one year ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.1
@Hero What do I do after this? Or is it already done? x^2  12x + 7 = 0 x^2  12x = 7 x^2  12x + (12/2)^2 = (12/2)^2  7 x^2  12x + 36 = 36  7 (x  6)^2 = 29
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
Sorry If I was offensive, @Hero .
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
Finish solving for x @Emily778
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
Take the square root of both sides
 one year ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.1
Can you show me how? I am so confused:(
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
@Emily778 PLEASE read this CAREFULLY. Do you know how to come up with the number that you have to add to both sides to ake the left side into a perfect square?
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
to make the left side...typo
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
dw:1384666594334:dw
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
Emily, do you get it conceptually?
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
Add 6 to both sides to finish solving for x
 one year ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.1
so, like this @Hero (x6)^2+6=29+6?
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
@Emily778, please observe what I did above first
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
I think you missed that last bit I posted in a drawing
 one year ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.1
oh, you have to square root first?
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
Yes you can't do anything until you take the square root of both sides.
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
@SolomonZelman, I assure you that we're supposed to add 36 to both sides. I wouldn't tell you anything wrong here.
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
If you don't believe me, I have ways of convincing you.
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
For one, I know you would never argue with WolframAlpha.
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
Hero, how does 36 make the left side into a perfect square, it is \[x^2+12x+7=0\]
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
Hang on, @SolomonZelman, WolframAlpha is undefeated.
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
I meant\[x^212x+7=0\]
 one year ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.1
okay, so it's actually x6+6=+=sqrt29=6?
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
Well yes it is then.
 one year ago

nincompoop Group TitleBest ResponseYou've already chosen the best response.1
omg don't argue with @Hero
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
@Hero, I am sorry to say this, but you have to rvw over some staff.
 one year ago

nincompoop Group TitleBest ResponseYou've already chosen the best response.1
he is correct and I am telling you it
 one year ago

Emily778 Group TitleBest ResponseYou've already chosen the best response.1
@hero okay, so it's actually x6+6=+=sqrt29=6?
 one year ago

nincompoop Group TitleBest ResponseYou've already chosen the best response.1
NOOOOOOOOOOOOOOO
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
Do you guys know how to complete the square, you don't need any online calculator for this. Idk how to even tell you this. you help with hard staff that I have no clue about, and make a simple error, in completing a square.
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
Don't tell me 1+1=4
 one year ago

nincompoop Group TitleBest ResponseYou've already chosen the best response.1
I know I do not need a calculator and I know he is correct
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
Notice that wolframalpha says to add 36 to both sides.
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
In this here link: http://tr.im/4klyc
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
maybe you put in 7, instead of +7.
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
OK, when you subtract 7, but you can just add 29, without subtracting 7.
 one year ago

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

Emily778 Group TitleBest ResponseYou've already chosen the best response.1
Thankyou! Is that it @Hero
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
There's only one correct way to do it @SolomonZelman. Wolframalpha shows the steps. Go review them.
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
@Emily778, I think you have it but review your symbology for mistakes and check the link on WolframAlpha
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
@Hero it wastes a step on subtracting 7 from both sides, you still get the same thing, \[x^212+36=29\] Do you see my point?
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
Do you guys just argue, or actually READ MY REPLIES?
 one year ago

nincompoop Group TitleBest ResponseYou've already chosen the best response.1
solomon, study more before you question
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
@nincompoop, you obviously didn't understand what i said.
 one year ago

nincompoop Group TitleBest ResponseYou've already chosen the best response.1
just study
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
Do you understand what I said, I don't need to study, I am fine.
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
@SolomonZelman, there's a difference between wasting steps and skipping steps.
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
Skipping steps leads to confusion
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
I am not saying the Wolframalpha is wrong, it just has a different way of showing... Yes, my bad, perhaps I skipped it, not wasted.... My teacher told me that both ways are valid, and to me that makes perfect sense. And YES, instead of arguing lets continue studying.
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
I still think though, that emily didn't get it conceptually.
 one year ago

nincompoop Group TitleBest ResponseYou've already chosen the best response.1
she never does...
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
That was quite offensive.
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
Yes, but some things can be figured out through selfstudy, observation and understanding. One thing is for sure. She surely won't get it if she is fed incorrect info.
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
True, and I was trying to ask emily if she figured out the first step(s) in completing the square.
 one year ago

nincompoop Group TitleBest ResponseYou've already chosen the best response.1
doubt it
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
Yes, me too, that's why I kept on asking that.
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
By the way @SolomonZelman, I'm fully aware of your method of doing it. But I abandoned it after I realized that steps were being skipped. It is wrong for teachers to teach it that way.
 one year ago

nincompoop Group TitleBest ResponseYou've already chosen the best response.1
couldn't agree more
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
Well, not that they taught me that, but didn't get any points off.
 one year ago

nincompoop Group TitleBest ResponseYou've already chosen the best response.1
it's cool can't teach someone about skipping when that person barely knows anything to begin with
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
I don't really see the difference between subtracting seven at first or not. To me it makes perfect sense to do my way.
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
I see your point though....
 one year ago

nincompoop Group TitleBest ResponseYou've already chosen the best response.1
1+1 = 4 though
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
And she still hasn't figure it out conceptually, just got the answer and left.
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
@nincompoop, actually in biology that could be true, like when parents (or future parents) combine or whatever the word for that is... LIKE twins.
 one year ago

nincompoop Group TitleBest ResponseYou've already chosen the best response.1
it's called precision
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
\(\huge {\color{green} {Yup,} }\) forgot the name for this, I learned that last year.
 one year ago

nincompoop Group TitleBest ResponseYou've already chosen the best response.1
anyway, good night
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
you too!
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
\(\huge {\color{green} {H} }\)\(\huge {\color{blue} {a} }\)\(\huge {\color{red} {v} }\)\(\huge {\color{orange} {e} }\) \(\huge {\color{purple} {a} }\) \(\huge {\color{lightblue} {n} }\)\(\huge {\color{grey} {i} }\)\(\huge {\color{brown} {g} }\)\(\huge {\color{lightgreen} {h} }\)\(\huge {\color{yellow }{t} }\)\(\huge {\color{darkgreen } {!} }\)
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
The difference between the methods is, one is systematic, and the other is not. The nonsystematic method is an approach that some would refer to as improper methodology.
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
\[\(\huge {\color{green} {B^{Y^{E ^{!}}}} }\)\]
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
Didn't delete the parenthesis....
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
The method I use can be generalized to this: You begin with x^2 + bx  c = 0 add c to both sides: x^2 + bx = c Then add (b/2)^2 to both sides: x^2 + bx + (b/2)^2 = (b/2)^2 + c
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
This is a systematic approach and you end up with (x + b/2)^2 = b^2/4 + c
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
Well, then improper methodology just shows that the person who did the steps is SMART.
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
Now let's see @SolomonZelman explain his method in a systematic, generalized manner.
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
I would just use an example similar to the one we solved just now.
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
Examples are not generalized. And they don't show the systematic methodology.
 one year ago

Hero Group TitleBest ResponseYou've already chosen the best response.1
Systematic methods have a better chance of being understood than nonsystematic methods.
 one year ago

SolomonZelman Group TitleBest ResponseYou've already chosen the best response.1
OK, I already said that I agree that to start teaching, systematic.... but not using it still shows that the solver is smarter.
 one year ago
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