a> x=13/12:2/3=13/8. vậy x=13/8
b>x=5/4 nhân 5/4=25/16. vậy...
c>x=7/4+1/2=9/4. vậy x=+-9/4
d>x=x=1-1/4=3/4. vậy...
a) \(0,5-\frac{2}{3}x=\frac{-7}{12}\)
\(\frac{1}{2}-\frac{2}{3}x=\frac{-7}{12}\)
\(\frac{2}{3}x=\frac{1}{2}-\frac{-7}{12}\)
\(\frac{2}{3}x=\frac{13}{12}\)
\(x=\frac{13}{12}:\frac{2}{3}\)
\(x=\frac{13}{8}\)
b) \(\frac{3}{4}-x:\frac{5}{4}=\frac{-1}{2}\)
\(x:\frac{5}{4}=\frac{3}{4}-\frac{-1}{2}\)
\(x:\frac{5}{4}=\frac{5}{4}\)
\(x=\frac{5}{4}.\frac{5}{4}\)
\(x=\frac{25}{16}\)
c) \(\left|x-\frac{1}{2}\right|-\frac{1}{4}=\frac{3}{2}\)
\(\left|x-\frac{1}{2}\right|=\frac{3}{2}+\frac{1}{4}\)
\(\left|x-\frac{1}{2}\right|=\frac{7}{4}\)
\(\Rightarrow\orbr{\begin{cases}x-\frac{1}{2}=\frac{7}{4}\\x-\frac{1}{2}=\frac{-7}{4}\end{cases}\Rightarrow\orbr{\begin{cases}x=\frac{9}{4}\\x=\frac{-5}{4}\end{cases}}}\)
Vậy x = 9/4 hoặc x = -5/4
d) \(\left|1-x\right|=\frac{1}{4}\)
\(\Rightarrow\orbr{\begin{cases}1-x=\frac{1}{4}\\1-x=\frac{-1}{4}\end{cases}\Rightarrow\orbr{\begin{cases}x=\frac{3}{4}\\x=\frac{5}{4}\end{cases}}}\)
Vậy x = 3/4 hoặc 5/4