Why is $4x^2 -3y^2 + 8x +12y-4 =0$ not a valid hyperbola?

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The equation I want to graph is: $$4x^2 -3y^2 + 8x +12y-4 =0$$

My textbook says that the above equation has no graph.

Yet, I rearranged it to the following:

$$\frac{(y-2)^2}{(2/\sqrt3)^2} - \frac{(x+1)^2}{1^2} = 1^2$$

Therefore, I thought it was a hyperbola. I know I've made a mistake in the rearrangement, as the two equations produce different graphs in Desmos. However, both equations produce hyperbolas, which contradicts my textbook.

Where am I going wrong? Thanks.

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If the book indeed says "no graph", it is wrong.

Because when plugging $(10,0)$, you get a positive value, and when plugging $(0,10)$, a negative one. Hence there are two regions of opposite signs and there must be a continuous curve in-between.

But my bet is that the book meant something different.


Note that when $x,y$ are both large, the equation virtually reduces to

$$2x=\pm\sqrt3y$$ which gives the directions of the asymptotes of the… hyperbola.

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$4(x+1)^2-3(y-2)^2=-4 \\ \displaystyle \Rightarrow \frac{3(y-2)^2}{4} - (x+1)^2=1$