Page 82 - Calculus for the Clueless, Calc II
P. 82

Just like with the ellipse, let's clarify the location of the vertices. In this case, the vertices occur north-south of
         the center (-7,6). So the x value of the vertices is the same as the center, x = -7. Substituting, we get






         The vertices are (-7,6 ± 5 ).
                                 1/2

         For the same reason, the foci, always on the axis through the vertices, are (-7,6 ± 22 ). The asymptotes and the
                                                                                         1/2
         sketch are the same!!

         Example 13—

         Sketch and discuss 25X  - 4y  + 50x - 12y + 116 = 0.
                               2
                                     2
         For the last time, we will complete the square, again a little bit differently.





















         Center (-1,-3/2); vertices              ; foci                 ; asymptotes                              .

        Sometimes we have a puzzle. Given some information, can we find the equation? You must always draw the
        picture and relate the picture to its equation.
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