SOLUTION: Find the center of an ellipse with the equation {{{9x^2 + 16y^2 - 18x + 64y = 71}}}

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Question 33194: Find the center of an ellipse with the equation 9x%5E2+%2B+16y%5E2+-+18x+%2B+64y+=+71
Answer by mukhopadhyay(490) About Me  (Show Source):
You can put this solution on YOUR website!
9x^2+16y^2-18x+64y=71
=> 9(x^2-2x)+16(y^2+4y) = 71
=> 9[(x-1)^2-1]+16[(y+2)^2-4] = 71
=> 9(x-1)^2+16(y+2)^2 = 71+9+64
=> 9(x-1)^2+16(y+2)^2 = 144 (same as 12^2)
=> (x-1)^2/4^2 + (y+2)^2/3^2 = 1
The center of an ellipse of form (x-h)^2/a^2 + (y-k)^2/b^2 = 1 is at (h,k)
So, the center of the specified ellipse is at (1,-2).