1. \(\frac{25}{100}x+x-\frac{1}{5}x=\frac{1}{5}\)
\(\Leftrightarrow\frac{1}{4}x+x-\frac{1}{5}x=\frac{1}{5}\)
\(\Leftrightarrow\left(\frac{1}{4}+1-\frac{1}{5}\right)x=\frac{1}{5}\)
\(\Leftrightarrow\frac{21}{20}x=\frac{1}{5}\)
\(\Leftrightarrow x=\frac{1}{5}:\frac{21}{20}\)
\(\Leftrightarrow x=\frac{4}{21}\)
2. \(\frac{2}{3}x-\frac{1}{2}x=\frac{3}{5}\)
\(\Leftrightarrow\frac{1}{6}x=\frac{3}{5}\)
\(\Leftrightarrow x=\frac{3}{5}:\frac{1}{6}\)
\(\Leftrightarrow x=\frac{18}{5}\)
3. \(\frac{2}{5}x-1\frac{1}{2}x+x=\frac{1}{3}\)
\(\Leftrightarrow\left(\frac{2}{5}-1\frac{1}{2}+1\right)x=\frac{1}{3}\)
\(\Leftrightarrow-\frac{1}{10}x=\frac{1}{3}\)
\(\Leftrightarrow x=-\frac{10}{3}\)
4. \(\left(x+\frac{2}{7}\right)\left(\frac{2}{3}-2x\right)=0\)
\(\Leftrightarrow\left[\begin{array}{nghiempt}x+\frac{2}{7}=0\\\frac{2}{3}-2x=0\end{array}\right.\) \(\Leftrightarrow\left[\begin{array}{nghiempt}x=-\frac{2}{7}\\x=\frac{1}{3}\end{array}\right.\)
1) \(25\%x+x-\frac{1}{5}x=\frac{1}{5}\)
\(\Rightarrow\frac{1}{4}x+x-\frac{1}{5}x=\frac{1}{5}\)
\(\Rightarrow x.\left(\frac{1}{4}+1-\frac{1}{5}\right)=\frac{1}{5}\)
\(\Rightarrow x.\frac{21}{20}=\frac{1}{5}\)
\(\Rightarrow x=\frac{1}{5}:\frac{21}{20}\)
\(\Rightarrow x=\frac{4}{21}\)
2) \(\frac{2}{3}x-\frac{1}{2}x=\frac{3}{5}\)
\(\Rightarrow x.\left(\frac{2}{3}-\frac{1}{2}\right)=\frac{3}{5}\)
\(\Rightarrow x.\frac{1}{6}=\frac{3}{5}\)
\(\Rightarrow x=\frac{3}{5}:\frac{1}{6}\)
\(\Rightarrow x=\frac{18}{5}\)
3) \(\frac{2}{3}x-1\frac{1}{2}x+x=\frac{1}{3}\)
\(\Rightarrow x.\left(\frac{2}{5}-1\frac{1}{2}+1\right)=\frac{1}{3}\)
\(\Rightarrow x.\left(-\frac{1}{10}\right)=\frac{1}{3}\)
\(\Rightarrow x=\frac{1}{3}:\left(-\frac{1}{10}\right)\)
\(\Rightarrow x=-\frac{10}{3}\)
4) \(\left(x+\frac{2}{7}\right).\left(\frac{2}{3}-2x\right)=0\)
\(\Rightarrow\left[\begin{array}{nghiempt}x+\frac{2}{7}=0\\\frac{2}{3}-2x=0\end{array}\right.\)
\(\Rightarrow\left[\begin{array}{nghiempt}x=-\frac{2}{7}\\x=\frac{1}{3}\end{array}\right.\)
1 . 25%x + x - \(\frac{1}{5}\)x = \(\frac{1}{5}\)
\(\frac{1}{4}\)x + 1x - \(\frac{1}{5}\)x = \(\frac{1}{5}\)
x ( \(\frac{1}{4}+1-\frac{1}{5}\) ) = \(\frac{1}{5}\)
x \(\frac{21}{20}\)= \(\frac{1}{5}\)
x = \(\frac{1}{5}:\frac{21}{20}\)
x = \(\frac{4}{21}\)
2 . \(\frac{2}{3}x-\frac{1}{2}x=\frac{3}{5}\)
\(\left(\frac{2}{3}-\frac{1}{2}\right)x=\frac{3}{5}\)
\(\frac{1}{6}x=\frac{3}{5}\)
\(x=\frac{3}{5}:\frac{1}{6}\)
\(x=\frac{18}{5}\)
Mik ngại viết theo kiểu phân số nên bạn thông cảm nha :
2/5x - 1 1/2x + x = 1/3
2/5x - 3/2x + 1x = 1/3
( 2/5 - 3/2 + 1 )x = 1/3
-1/10x = 1/3
x = 1/3 : -1/10
x = 13/30
4 . ( x + 2/7 ) . ( 2/3 - 2x ) = 0
=> x + 2/7 = 0 hoặc 2/3 - 2x = 0
Ta xét : x + 2/7 = 0
x = 0 - 2/7
x = -2/7
Ta xét : 2/3 - 2x = 0
2x = 2/3 - 0
2x = 2/3
x = 2/3 : 2
x = 1/3
1. \(25\%x+x-\frac{1}{5}x=\frac{1}{5}\)
\(x\left(\frac{1}{4}+1-\frac{1}{5}\right)=\frac{1}{5}\)
\(\frac{21x}{20}=\frac{1}{5}\)
\(\frac{21x}{20}=\frac{4}{20}\)
\(21x=4\Rightarrow x=\frac{4}{21}\)
2. \(\frac{2}{3}x-\frac{1}{2}x=\frac{3}{5}\)
\(x\left(\frac{2}{3}-\frac{1}{2}\right)=\frac{3}{5}\)
\(\frac{x}{6}=\frac{3}{5}\)
\(\frac{5x}{30}=\frac{18}{30}\)
\(5x=18\Rightarrow x=\frac{18}{5}\)
3. \(\frac{2}{5}x-1\frac{1}{2}x+x=\frac{1}{3}\)
\(x\left(\frac{2}{5}-1\frac{1}{2}+1\right)=\frac{1}{3}\)
\(\frac{-x}{10}=\frac{1}{3}\)
\(\frac{-3x}{30}=\frac{10}{30}\)
\(-3x=10\Rightarrow x=-\frac{10}{3}\)
4. \(\left(x+\frac{2}{7}\right)\left(\frac{2}{3}-2x\right)=0\)
*\(x+\frac{2}{7}=0\Rightarrow x=-\frac{2}{7}\)
*\(\frac{2}{3}-2x=0\Rightarrow x=\frac{1}{3}\)
Vậy \(x=-\frac{2}{7};x=\frac{1}{3}\)
