Question 615277
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If A = C, and neither is zero, you have a circle.

If A is not equal to C, and neither is zero, but they are both the same sign, then ellipse.

If A and C have different signs, and neither is zero, then hyperbola.

If either A or C is zero, but not both, then parabola.

If both A and C are zero, then straight line.

John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
My calculator said it, I believe it, that settles it
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