Câu 2 :
\(a,\dfrac{3}{4}x-\dfrac{1}{2}=\dfrac{-5}{6}\)
\(\dfrac{3}{4}x=\dfrac{-1}{3}\)
\(x=\dfrac{-1}{3}:\dfrac{3}{4}\)
\(x=\dfrac{-4}{9}\)
\(b,\left(75\%x-2\dfrac{1}{2}\right).\dfrac{2}{3}=\dfrac{1}{8}\)
\(\left(\dfrac{3}{4}x-\dfrac{5}{2}\right).\dfrac{2}{3}=\dfrac{1}{8}\)
\(\dfrac{3}{4}x-\dfrac{5}{2}=\dfrac{1}{8}:\dfrac{2}{3}\)
\(\dfrac{3}{4}x-\dfrac{5}{2}=\dfrac{3}{16}\)
\(\dfrac{3}{4}x=\dfrac{3}{16}-\dfrac{5}{2}\)
\(\dfrac{3}{4}x=\dfrac{-37}{16}\)
\(x=\dfrac{-37}{12}\)
Câu 2:
a: \(\Leftrightarrow x\cdot\dfrac{3}{4}=\dfrac{-5}{6}+\dfrac{1}{2}=\dfrac{-5}{6}+\dfrac{3}{6}=\dfrac{-1}{3}\)
hay x=-4/9
b: \(\Leftrightarrow\left(x\cdot\dfrac{3}{4}-\dfrac{5}{2}\right)=\dfrac{1}{8}:\dfrac{2}{3}=\dfrac{3}{16}\)
\(\Leftrightarrow x\cdot\dfrac{3}{4}=\dfrac{3}{16}+\dfrac{5}{2}=\dfrac{3}{16}+\dfrac{40}{16}=\dfrac{43}{16}\)
hay x=43/12