✔ 最佳答案
1)16x²+25y²-96x-256=0
16(x² - 6x) +25y²-256=0
16(x² - 6x+9) +25y²-256-144=0
16(x - 3)^2 +25y²-256-144=0
16(x - 3)^2 +25y² = 400
ellipse
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2)x²-xy+y=0
有無打少左野??
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3)25x²+25y²-16=0
25x²+25y² = 16
x²+y² = 16/25
circle
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4)x²+y²-4ax-4by+4a²+4b²-r²=0
x²-4ax+4a² + y²-4by+4b²-r²=0
(x-2a)^2 + (y-2b)^2-r²=0
(x-2a)^2 + (y-2b)^2 = r²
circle
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5)x²+2xy+y²-6x-2y-3=0
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3x²/9-y²/25=1
雙曲線