Question

[Hoàng Văn Anh]

tim x y z biết

a,4x^2+9y^2+4x-24y+17=0

b,2x^2+2y^2+z^2+2xy-2xz-6y+9=0

c,x^2+2y+2xy+2x+6y+5=0

Answer 1

[Nguyễn Phương Uyên]

\(a,4x^2+9y^2+4x-24y+17=0\)

\(\Rightarrow\left(4x^2+4x+1\right)+\left(9y^2-24y+16\right)=0\)

\(\Rightarrow\left(2x+1\right)^2+\left(3y-4\right)^2=0\)

\(\left(2x+1\right)^2\ge0;\left(3y-4\right)^2\ge0\)

\(\Rightarrow\hept{\begin{cases}\left(2x+1\right)^2=0\\\left(3y-4\right)^2=0\end{cases}\Rightarrow\hept{\begin{cases}2x+1=0\\3y-4=0\end{cases}\Rightarrow}\hept{\begin{cases}x=-\frac{1}{2}\\y=\frac{4}{3}\end{cases}}}\)

Answer 2

[Hiếu Mai]

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