Trying to solve conic for ellipse equation

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I'm trying to find out what conic the following equation represents.

$9x^2+4y^2+18x-16y+24 = 0$

I know that the general ellipse equation is $(x^2)/a + (y^2)/b = 1.$

I got $9(x+1)^2 + 4(y-2)^2 = 1$, but I am not sure what to do next.

For example if I had some number instead of $1$, I could easily divide everything and get the "correct" equation pattern, but since I already have a $1$ on the right, I am not sure what to do.

Regards, L.K.

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If, for some reason, what you say you get is correct then

$$9(x+1)^2+4(y-2)^2=1\iff \frac{(x+1)^2}{\frac19}+\frac{(y-2)^2}{\frac14}=1\implies a=\frac13\;,\;b=\frac12$$

Remember that for any non-zero number $\;a\;$ , we have

$$a=\frac1{\frac1a}$$