Question

Tìm x,y biết

| 2x-5|+| 3y+1 |=0

Answer 1

\(\left|2x-5\right|+\left|3y+1\right|=0\)

\(\left\{{}\begin{matrix}\left|2x-5\right|\ge0\\\left|3y+1\right|\ge0\end{matrix}\right.\)

\(\Rightarrow\left|2x-5\right|+\left|3y+1\right|\ge0\)

Dấu "=" xảy ra khi:

\(\left\{{}\begin{matrix}\left|2x-5\right|=0\\\left|3y+1\right|=0\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=\dfrac{2}{5}\\y=-\dfrac{1}{3}\end{matrix}\right.\)

Answer 2

Bài này dễ :V

\(\left|2x-5\right|\ge0;\left|3y+1\right|\ge0\)

nên 2x-5=0 ; 3y+1=0 => x=\(\dfrac{5}{2}\);y=\(\dfrac{-1}{3}\)