*To*: mathgroup@smc.vnet.net*Subject*: [mg11162] Re: [mg11088] Re: Conic Sections and Quadric Surfaces*From*: Carlo Infante <cinfante@worldnet.att.net>*Date*: Mon, 23 Feb 1998 21:41:23 -0500

Does writing the equation for the ellipse in parametric form help? Carlo Infante =================================== >> Ref: Introduction to Linear Algebra- 4th ed. Johnson,Riess and Arnold >> (page 35) >> >> Find the equation of the conic section passing through the five points >> (-1,0),(0,1),(2,2),(1,-1), (0,-3). Display the graph of the conic. >> >> When I try to set up the augmented matrix I get two (2) indeterminate >> rows which >> prevents my proceeding with the method outlined in the textbook Linear >> Algebra with Mathematica by E. Johnson page 58 to 59. How can I get >> around this?The equation to satisfy (an ellipse) is ax^2 + bxy + cy^2 + >> dx + ey + f =0. Is there some other technique I can use to find the >> equation given sevral points? >> I am presently playing around with Fit[ data,{etc}] but I only know how >> to fit quadratics. Thank you in advance. >> Manuel Avalos >> MAvalosjr@aol.com Carlo Infante cinfante@worldnet.att.net