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Destinyyyy
 one year ago
Help..
Destinyyyy
 one year ago
Help..

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Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0Solve by completing the square. x^2+11x9=0

Michele_Laino
 one year ago
Best ResponseYou've already chosen the best response.1we can write this: \[\Large {x^2} + 11x  9 = {x^2} + 11x + \frac{{121}}{4}  \frac{{121}}{4}  9\]

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0Um where did you get 121 and 4 from???

Michele_Laino
 one year ago
Best ResponseYou've already chosen the best response.1since we have this: \[\Large {\left( {x + \frac{{11}}{2}} \right)^2} = {x^2} + 11x + \frac{{121}}{4}\]

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0Um okay.. Can you start at the beginning on how to solve this?

Michele_Laino
 one year ago
Best ResponseYou've already chosen the best response.1I rewrite the left side of your equation, adding and subtracting the same quantity, namely 121/4, so I get this equation: \[\Large {x^2} + 11x + \frac{{121}}{4}  \frac{{121}}{4}  9 = 0\]

Michele_Laino
 one year ago
Best ResponseYou've already chosen the best response.1then, I use this identity: \[\Large {\left( {x + \frac{{11}}{2}} \right)^2} = {x^2} + 11x + \frac{{121}}{4}\]

Michele_Laino
 one year ago
Best ResponseYou've already chosen the best response.1so I can rewrite your starting equation, as below: \[\Large {\left( {x + \frac{{11}}{2}} \right)^2}  \frac{{121}}{4}  9 = 0\]

Michele_Laino
 one year ago
Best ResponseYou've already chosen the best response.1next, I nothe that: \[ \Large  \frac{{121}}{4}  9 =  \frac{{157}}{4}\]

Michele_Laino
 one year ago
Best ResponseYou've already chosen the best response.1after a substitution, I get this: \[\Large {\left( {x + \frac{{11}}{2}} \right)^2}  \frac{{157}}{4} = 0\]

Michele_Laino
 one year ago
Best ResponseYou've already chosen the best response.1or: \[\Large {\left( {x + \frac{{11}}{2}} \right)^2} = \frac{{157}}{4}\]

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0Uh? Im here x^2+11x9=0 (x+11/2)^2 9=0 x^2+ 121/4 9=0 I dont understand past that

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0Ive been using this method or factoring https://www.youtube.com/watch?v=bclm1tJB3g

Michele_Laino
 one year ago
Best ResponseYou've already chosen the best response.1In order to get an equivalent equation, I have to add and contemporarily I have to subtract 121/4, namely the same quantity

Michele_Laino
 one year ago
Best ResponseYou've already chosen the best response.1so I get this equation: \[\Large {x^2} + 11x + \frac{{121}}{4}  \frac{{121}}{4}  9 = 0\]

Michele_Laino
 one year ago
Best ResponseYou've already chosen the best response.1the first three terms at the left side are the square of the subsequent binomial: \[\Large {\left( {x + \frac{{11}}{2}} \right)^2}\]

Michele_Laino
 one year ago
Best ResponseYou've already chosen the best response.1so, substituting, I can write this: \[\Large {\left( {x + \frac{{11}}{2}} \right)^2}  \frac{{121}}{4}  9 = 0\]

Michele_Laino
 one year ago
Best ResponseYou've already chosen the best response.1next I do this computation: \[\Large  \frac{{121}}{4}  9 =  \frac{{157}}{4}\]

Michele_Laino
 one year ago
Best ResponseYou've already chosen the best response.1and, again I substitute: \[\Large {\left( {x + \frac{{11}}{2}} \right)^2}  \frac{{157}}{4} = 0\]

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0What? I seriously do not understand. How in the world do you get 157? I understand that (x+ 11/2)^2 equals x^2 +121/4 .. I assume the 11 over 2 is 11x divided by 2 which cant happen so it stays as a fraction. You said something about subtracting 121/4 and I assumed you meant to the other side of the equal sign but wasn't entirely sure. Im really trying to follow what your saying and I'm good in math but all this makes absolutely no sense so far.

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0Im still where I was earlier.

Michele_Laino
 one year ago
Best ResponseYou've already chosen the best response.1here is more details of my computation: dw:1440704847919:dw

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0Where are you getting the negative in front of 121/4 from?

Michele_Laino
 one year ago
Best ResponseYou've already chosen the best response.1since I have used +121/4 in order to have the square of binomial, then the remaining 121/4 has to be summed to 9

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0"then the remaining 121/4 has to be summed to 9" ??

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2according to the video u watched 1st) move the constant term to the right side 2nd) divide `b` by 2 and then take square of the result in that case you you would `add` \[\rm (\frac{ b }{ 2})^2\]to the right side but if you keep the constant term at left side then you should subtract

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0@Michele_Laino I put question marks at the end saying what to it... @Nnesha yeah I tried that and 11 divided by 2 is 5.5 so I stopped

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2http://prntscr.com/89mc1g http://prntscr.com/89mbs3 so you need to be careful about this

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2that's right 5.5 which is same as 11/2 u got the decimal but he/she is keptt the fraction form but same thing! :=)

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0Yes I understood that part. After that I get lost

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2so do you want to move the constant to the right side or do you want to keep it at left side ?

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0The video says to move it to the right.. But I honestly dont know.

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2you will get the same answer

Michele_Laino
 one year ago
Best ResponseYou've already chosen the best response.1we have to add to both sides +157/4, so we get this: \[\Large {\left( {x + \frac{{11}}{2}} \right)^2}  \frac{{157}}{4} + \frac{{157}}{4} = \frac{{157}}{4}\]

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0I understand the adding to both sides but I dont get where you got 157 from

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2ye so doesn't matter you can move the constant term to right side at the beginning or after completing the square of (x^2+11x)

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2when you add 9 and 121/4 you will get that 157/4

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2\[\huge\rm x^2+11x=9\] divide b by 2 and then take square of that result

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0Do you mean (x^2+121/4) or 11/2= 5.5^2= 30.25

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0Can you explain this more " when you add 9 and 121/4 you will get that 157/4 " because im not getting 157... 9+121= 130 .. I dont see where the plus sign came from.

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2yes right \[\huge\rm (x+5.5)^2=9+(5.5)^2\] okay i will

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2dw:1440706398196:dw there is one under 9 so 4 is the common denominator right ?

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0Okay now I understand where the 157 come from.

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.05.5*5.5= 30.25 +9= 39.25

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2yes right common denominator multiply the numerator of first fraction by the denominator of 2nd fraction multiply the numerator of 2nd fraction by the denominator of first fraction dw:1440706515919:dw

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0Can you write it down how to solve this on paper and take a picture and post it on here? Maybe I can actually understand then

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2yes right 39.25 is same as 157/4

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2and after that i'm pretty sure you know how to solve for x right :D

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0Yeah if I knew what the equation was.. All I have written down in front of me is x^2+11x+ ____=9+____ x^2+11x9=0 (x+11/2)^2 9=0 x^2+ 121/4 9=0

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2uhoh why it's negative 9 at right sdie ?

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0Its suppose to be a positive mistype

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0I have x^2 157/4 =0

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2cuz here dw:1440706885310:dw like this

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2or you can skip that factor step shortcut!dw:1440707138935:dw

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2divide `b` by 2 write that in the parentheses square would be to (x+b/2)^2 but you would add square of (b/2)^2 to the right side

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2that's another of saying x^2+!1x+ 30.25 = (x+5.5)^2 x+5.5 is a factor of x^2+!1x+30.25

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2ask question if you didn't get what i mean ......

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2this is good example here \[\huge\rm x^2+bx+C=0\]\[\huge\rm x^\color{Red}{2}+Bx=C\]\[\huge\rm (x+\frac{ b }{ 2})^\color{red}{2}=C +(\frac{ b }{ 2 })^2\]

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0Okay.. I have (x+5.5)^2=+ 39.25 square root x+5.5= + square root 39.25 x+5.5=+

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2yes right \[x+\frac{ 11 }{ 2 } = \pm \sqrt{ \frac{ {157} }{ 4 }}\] or you can keep it in fraction form

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2add you can see 4 is perfect square root so can take square of 4

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0Okay I get it.. I think

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2if keep the decimal we will not be able to know if there is any perfect square root or not

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0The final answer is x= 11/2 + square root 157/ 4

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2okay practice 2 or 3 time you will definitely understand

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0Opp negative in front of the 11

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2\[x+\frac{ 11 }{ 2 } = \pm \sqrt{ \frac{ {157} }{ 4 }}\] \[x+\frac{ 11 }{ 2 } =\frac{ \sqrt{157} }{ \sqrt{4}}\] square root of 4 is 2 right

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2\[\huge\rm x=\frac{ 11 }{ 2 } \pm \frac{ \sqrt{157} }{ 2}\] so same denominator
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