Question

Convert from general form to standard form x^2 + 4y^2 + 6x-40y+9 =0​

Answer 1

$x^2 + 4y^2 + 6x-40y+9 =0\\x^2 + 6x+9+4y^2-40y=0\\x^2+6x+9+4y^2-40y+100-100=0\\(x+3)^2+(2y-10)^2=100$

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