Question 708061
The ellipse is centered at (-1, -3). The length of its horizontal axis is 6, and the length of its vertical axis is 4. What is the equation for the ellipse?
<pre>
Since the horizontal axis is longer, the equation is 

{{{(x-h)^2/a^2}}}{{{""+""}}}{{{(y-k)^2/b^2}}}{{{""=""}}}{{{1}}}

[If it had been shorter, the a and b would be swapped].

(h,k) = the center

a = half the longer axis = {{{1/2}}}*6 = 3

b = half the shorter axis = {{{1/2}}}*4 = 2

{{{(x-(-1))^2/3^2}}}{{{""+""}}}{{{(y-(-3))^2/2^2}}}{{{""=""}}}{{{1}}}

{{{(x+1)^2/9}}}{{{""+""}}}{{{(y+3)^2/4}}}{{{""=""}}}{{{1}}}

Edwin</pre>