Câu 2: Trang 28 sách toán VNEN lớp 6 tập 2
Tìm x, biết:
a) $x\;-\;\frac{3}{5} = \frac{1}{2}$.
b) $\frac{-5}{8}\;-\;x = \frac{7}{24}\;+\;\frac{-1}{6}$.
Bài Làm:
a) $x\;-\;\frac{3}{5} = \frac{1}{2} $
$\Rightarrow x = \frac{1}{2}\;+\;\frac{3}{5}$.
$\Rightarrow x = \frac{5}{10}\;+\;\frac{6}{10}$.
$\Rightarrow x = \frac{5\;+\;6}{10}$.
$\Rightarrow x = \frac{11}{10}$.
b) $\frac{-5}{8}\;-\;x = \frac{7}{24}\;+\;\frac{-1}{6}$.
$\Rightarrow -x = \frac{7}{24}\;+\;\frac{-1}{6}\;+\;\frac{5}{8}$.
$\Rightarrow x = -(\frac{7}{24}\;+\;\frac{-1}{6}\;+\;\frac{5}{8})$.
$\Rightarrow x = -(\frac{7}{24}\;+\;\frac{-4}{24}\;+\;\frac{15}{24})$.
$\Rightarrow x = -(\frac{7\;+\;(-4)\;+\;15}{24})$.
$\Rightarrow x = -(\frac{18}{24})$.
$\Rightarrow x = -(\frac{3}{4})$.