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The equation is included below and what im trying to find is the inverse function. I have already attempted to isolate x to no avail as I am unable to remove x from the absolute value block. 

y=−2|3x+1|−1

Furthermore i have also attempted to simply convert the equation to the following general form:

y=a[b(x−c)]^2+d

which gave me:

x=-2[(|3y+1|)^2]-1

which although seems to have the correct vertex, I am unsure about were the variable b would come from and am unsure about what I would do the the vertical compression/stretch and horizontal compression/stretch to obtain an inverse function with perfectly straight lines.

If possible please ensure that your answers are in the general form provided above and include an explanation for each step and how the variables were solved for.

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    What's the domain of your function? $y(x)$ is not invertible on $\mathbb{R}$ since it is not injective. – 2017-02-09
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    @needforhelp a domain has not been provided to me, and i do not know what the term "injective" means – 2017-02-09
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    Without restriction on the domain, there is no inverse function... – 2017-02-09
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    @imranfat i guess its a trick question then?, either way thanks for your time – 2017-02-09
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    As Need for help indicated, for an inverse to be a function, you cannot have two different x values for one y value. That's the problem with the given function – 2017-02-09
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    @imranfat then why can y=x^2 have an inverse function? – 2017-02-09
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    @Mohammad Ali We say a function $f$ is injective if for all $x,y \in \operatorname{dom}(f)$, $f(x) = f(y)$ implies $x=y$. A necessary condition for a function $f : A \to B$ to have an inverse is that $f$ be injective. In this case, if you let $f(x) = -2 | 3x + 1 | -1$ and don't specify the domain, it is understood that $\operatorname{dom}(f)$ is the *largest* set for which the expression $-2 | 3x + 1 | -1$ makes sense. In this case, the expression makes sense for all $x \in \mathbb{R}$. But what should be the inverse of, say, $y = -10$ under $f$ ? That is, what should be $f^{-1}(-10)$ ? – 2017-02-09
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    @Mohammad Ali Note that $f(-11/6)$ and $f(7/6)$ both equal $-10$. But then $f^{-1}(-10)$ is not well defined, since you have *two* possibilities for it. – 2017-02-09
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    @needForHelp I see what you mean, thank you for your time, if you would like to post an answer stating that the question is impossible so i can mark it as correct to help inform others who may look at this, as at least i personally never look at comments when a question hasn't been answered – 2017-02-09

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