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anonymous
 one year ago
Please help =*(
anonymous
 one year ago
Please help =*(

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anonymous
 one year ago
Best ResponseYou've already chosen the best response.0If \[f(x)=12\frac{ x ^{2} }{ 2 }\] and f(2k)=2k what is one possible value for k?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0solve 2k = 12  (2k)^2/2

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0y cant the answer be 5?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0probably because you solved it wrong.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0k = 3 or 2 https://www.wolframalpha.com/input/?i=2k+%3D+12++%282k%29%5E2%2F2

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0dw:1435945239538:dw

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0why cant it be that?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0when you divide by 2k you have 12/2k 2k^2/2k =12/2k  k =12/2k k^2/k =122k^2/k

Owlcoffee
 one year ago
Best ResponseYou've already chosen the best response.1The problem with dividing an equations or even a function by the independant variable desired to solve for, you lose one of the values which is contained in the set of the solution. So, if you have: \[f:f(x)=12 \frac{ x^2 }{ 2 }\] And we are asked to find the value that the function takes when x is equal to 2k, or in other words f(2k). \[f(2k)=12\frac{ (2k)^2 }{ 2 }\] \[f(2k)=2k\] Then, knowing the value the function takes at the point "2k", we only need to find the value of "k" that satisfies this equation: \[2k=12\frac{ (2k)^2 }{ 2 }\] This has become a univariable equation but as a second degree polynomial expression, so what we will do is try to fix to the structure: \[ax^2+bx+c=0\] in this case, "k" is the variable so we will treat it as if it was a popular known "x" first off, getting rid of the denominator by performing the common denominator operation: \[2k=\frac{ 2(12)(2k)^2 }{ 2 }\] And multiply both sides by "2": \[2(2k)=2(12)(2k)^2\] And now, simplifying: \[4k=244k^2\] And taking it to the structure I mentioned earlier: \[4k^2+4k24=0\] And we can divide both sides by "4" in order to reduce the coefficients as much as possible: \[\frac{ 4k^2+4k24 }{ 4 }=\frac{ 0 }{ 4 }\] and simplifying: \[k^2+k6=0\] Now, in order to solve this we will have to use the general formula or also known as the "formula of bhaskara".

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0so the way i did it was wrong?

Owlcoffee
 one year ago
Best ResponseYou've already chosen the best response.1Yes, unfortunately :(
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