Question

Bài 1:Tìm cặp x,y thuộc Z biết:

a,|x-3y|5+|y+4|=0

b,|x+3y-1|+3|y+2|=0

Help me:)) gấp lắm mn ạ,thanks trước nha

Answer 1

\(\left|x-3y\right|5+\left|y+4\right|=0\)

\(\Leftrightarrow\left\{\begin{matrix}x-3y=0\\y+4=0\end{matrix}\right.\)\(\Leftrightarrow\left\{\begin{matrix}x=3y\\y=-4\end{matrix}\right.\)\(\Leftrightarrow\left\{\begin{matrix}x=-12\\y=-4\end{matrix}\right.\)

Vậy....

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\(\left|x+3y-1\right|+3\left|y+2\right|=0\)

\(\Leftrightarrow\left\{\begin{matrix}x+3y-1=0\\y+2=0\end{matrix}\right.\)\(\Leftrightarrow\left\{\begin{matrix}x=1-3y\\y=-2\end{matrix}\right.\)\(\Leftrightarrow\left\{\begin{matrix}x=7\\y=-2\end{matrix}\right.\)

Vậy .....

Answer 2

1,a)\(\left|x-3y\right|\)\(\ge\)0 => \(\left|x-3y\right|\).5 \(\ge\)0

\(\left|y+4\right|\)\(\ge\)0

Mà \(\left|x-3y\right|\)5+\(\left|y+4\right|\)=0

=> \(\left|y+4\right|\)=0 => y=-4

=> \(\left|x-3y\right|\)=0 => \(\left|x-3.-4\right|\)=0 => x= -12

Câu b làm tương tự.

Tick cho chụy nha!