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View Full Version : Ellipses 2y^2+5x^2+12y-20x+10=-18


Skoob43
Jan 9, 2011, 02:35 PM

galactus
Jan 10, 2011, 08:14 AM
Yes. And do what?

Write it in the form, \frac{(x-h)^{2}}{a^{2}}+\frac{(y-k)^{2}}{b^{2}}=1

If so, complete the square on x and y.

2y^{2}+12y+5x^{2}-20x=-28

Complete square:

5(x^{2}-4x+4)+2(y^{2}+6y+9)=10

5(x-2)^{2}+2(y+3)^{2}=10

Divide by 10:

\frac{(x-2)^{2}}{2}+\frac{(y+3)^{2}}{5}=1

The ellipse has center (2,-3), Minor axis length \sqrt{2} and major axis length \sqrt{5}