d: \(\Leftrightarrow4x^2-4x+1+y^2+10y+25=0\)
\(\Leftrightarrow\left(2x-1\right)^2+\left(y+5\right)^2=0\)
=>x=1/2 và y=-5
e: \(\Leftrightarrow9x^2+12x+4+4y^2+8y+4=0\)
\(\Leftrightarrow\left(3x+2\right)^2+\left(2y+2\right)^2=0\)
=>x=-2/3 và y=-1
d)Ta có \(4x^2+y^2-4x+10x+26=0\Leftrightarrow4x^2-4x+1+y^2+10x+25=0\Leftrightarrow\left(2x-1\right)^2+\left(y+5\right)^2=0\Leftrightarrow\left(2x-1\right)^2=\left(y+5\right)^2=0\Leftrightarrow x=\dfrac{1}{2},y=-5\)
e)Ta có \(9x^2+12x+4y^2+8y+8=0\Leftrightarrow9x^2+12x+4+4y^2+8y+4=0\Leftrightarrow\left(3x+2\right)^2+\left(2y+2\right)^2=0\Leftrightarrow\left(3x+2\right)^2=\left(2y+2\right)^2=0\Leftrightarrow x=-\dfrac{2}{3},y=-1\)