Find the centre, the lengths of the axes, eccentricity, foci of the following ellipse:

4x2 + 16y2 - 24x - 32y - 12 = 0

Given that we need to find the centre, lengths of axes, eccentricity and foci of the ellipse 4x2 + 16y2 - 24x - 32y - 120 = 0.



4x2 + 16y2 - 24x - 32y - 120 = 0


4(x2 - 6x + 9) + 16(y2 - 2y + 1) - 172 = 0


4(x - 3)2 + 16(y - 1)2 = 172




Comparing with the standard form


Centre = (p,q) = (3,1)


Here a2>b2


eccentricity(e) =






Length of the major axis 2a = 2() =


Length of the minor axis 2b =


Foci = (p±ae,q)


Foci =


Foci =


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