



 
Hi Sima, You want to put the equation into standard form: (x  a)^{2}/p^{2} + (y  b)^{2}/q^{2} = 1. The centre is then (a, b). To start, look at the two xterms, 3x^{2} + 18x = 3(x^{2} + 6x). I want to complete the square so I add 9 inside the parentheses. So to maintain the equality I also need to subtract 3 * 9 = 27 and hence I have
Thus the equation of the ellipse can be written
Now perform the same technique with the two yterms and then write the equation in standard form. Penny  


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