1: \(\left|3x-4\right|+\left|3y+5\right|=0\)
=>\(\left\{{}\begin{matrix}3x-4=0\\3y+5=0\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}3x=4\\3y=-5\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=\dfrac{4}{3}\\y=-\dfrac{5}{3}\end{matrix}\right.\)
2: \(\left|8,8x-50\right|:0,4=51\)
=>\(\left|8,8x-50\right|=51\cdot0,4=20,4\)
=>\(\left[{}\begin{matrix}8,8x-50=20,4\\8,8x-50=-20,4\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}8,8x=50+20,4=70,4\\8,8x=50-20,4=29,6\end{matrix}\right.\)
=>\(\left[{}\begin{matrix}x=8\\x=\dfrac{296}{88}=\dfrac{37}{11}\end{matrix}\right.\)
3: \(\left|x-1.38\right|+\left|2y+4,2\right|=0\)
=>\(\left\{{}\begin{matrix}x-1,38=0\\2y+4,2=0\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=1,38\\2y=-4,2\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=1,38\\y=-2,1\end{matrix}\right.\)
4: \(\left|x\right|-\dfrac{3}{5}=\dfrac{5}{9}\)
=>\(\left|x\right|=\dfrac{3}{5}+\dfrac{5}{9}=\dfrac{27}{45}+\dfrac{25}{45}=\dfrac{52}{45}\)
=>\(\left[{}\begin{matrix}x=\dfrac{52}{45}\\x=-\dfrac{52}{45}\end{matrix}\right.\)
5: \(\left|2x-5\right|=\dfrac{1}{2}\cdot2^6\)
=>\(\left|2x-5\right|=2^6:2=2^5=32\)
=>\(\left[{}\begin{matrix}2x-5=32\\2x-5=-32\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}2x=37\\2x=-27\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{37}{2}\\x=-\dfrac{27}{2}\end{matrix}\right.\)
6: \(\left|x+\dfrac{3}{5}\right|-\left|x-\dfrac{7}{3}\right|=0\)
=>\(\left|x+\dfrac{3}{5}\right|=\left|x-\dfrac{7}{3}\right|\)
=>\(\left[{}\begin{matrix}x+\dfrac{3}{5}=x-\dfrac{7}{3}\\x+\dfrac{3}{5}=-x+\dfrac{7}{3}\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}\dfrac{3}{5}=-\dfrac{7}{3}\left(loại\right)\\2x=\dfrac{7}{3}-\dfrac{3}{5}\end{matrix}\right.\)
=>\(2x=\dfrac{7}{3}-\dfrac{3}{5}=\dfrac{35}{15}-\dfrac{9}{15}=\dfrac{26}{15}\)
=>\(x=\dfrac{13}{15}\)
7: \(\left|x+\dfrac{1}{3}\right|=0\)
=>\(x+\dfrac{1}{3}=0\)
=>\(x=0-\dfrac{1}{3}=-\dfrac{1}{3}\)
8: \(\dfrac{1}{2}x+\dfrac{3}{5}=\dfrac{1}{2}\)
=>\(\dfrac{1}{2}x=\dfrac{1}{2}-\dfrac{3}{5}=\dfrac{5}{10}-\dfrac{6}{10}=-\dfrac{1}{10}\)
=>\(x=-\dfrac{1}{10}:\dfrac{1}{2}=-\dfrac{1}{10}\cdot2=-\dfrac{2}{10}=-\dfrac{1}{5}\)
1) \(\left|3x-4\right|+\left|3y+5\right|=0\)
\(\Rightarrow\left|3x-4\right|=0\) và \(\left|3y+5\right|=0\)
*) \(\left|3x-4\right|=0\)
\(3x-4=0\)
\(3x=4\)
\(x=\dfrac{4}{3}\)
*) \(\left|3y+5\right|=0\)
\(3y+5=0\)
\(3y=-5\)
\(y=-\dfrac{5}{3}\)
Vậy \(x=\dfrac{4}{3};y=-\dfrac{5}{3}\)
2) \(\left|8,8x-50\right|:0,4=51\)
\(\left|8,8x-50\right|=51.0,4\)
\(\left|8,8x-50\right|=20,4\)
\(\Rightarrow8,8x-50=20,4\) hoặc \(8,8x-50=-20,4\)
*) \(8,8x-50=20,4\)
\(8,8x=20,4+50\)
\(8,8x=70,4\)
\(x=\dfrac{70,4}{8,8}\)
\(x=8\)
*) \(8,8x-50=-20,4\)
\(8,8x=-20,4+50\)
\(8,8x=29,6\)
\(x=\dfrac{29,6}{8,8}\)
\(x=\dfrac{37}{11}\)
Vậy \(x=\dfrac{37}{11};x=8\)
3) \(\left|x-1.38\right|+\left|2y+4,2\right|=0\)
\(\Rightarrow\left|x-1,38\right|=0\) hoặc \(\left|2y+4,2\right|=0\)
*) \(\left|x-1,38\right|=0\)
\(x-1,38=0\)
\(x=1,38\)
*) \(\left|2y+4,2\right|=0\)
\(2y+4,2=0\)
\(2y=-4,2\)
\(y=\dfrac{-4,2}{2}\)
\(y=-2,1\)
Vậy \(x=1,38;y=-2,1\)
