\(9-x=\dfrac{8}{7}-\left(-\dfrac{7}{8}\right)\) -> Đề bài như này đúng ko?
\(9-x=\dfrac{113}{56}\)
\(x=9-\dfrac{113}{56}\)
\(x=\dfrac{391}{56}\)
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\(2x+\dfrac{1}{2}=\dfrac{7}{9}\)
\(2x=\dfrac{7}{9}-\dfrac{1}{2}\)
\(2x=\dfrac{5}{18}\)
\(x=\dfrac{5}{18}:2\)
\(x=\dfrac{5}{36}\)
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\(\dfrac{3}{4}-6x=\dfrac{7}{13}\)
\(6x=\dfrac{3}{4}-\dfrac{7}{13}\)
\(6x=\dfrac{11}{52}\)
\(x=\dfrac{11}{52}:6\)
\(x=\dfrac{11}{312}\)
Đề câu `1` chưa rõ bạn xem lại
`@ 2x + 1/2 =7/9`
`2x=7/9-1/2`
`2x=14/18-9/18`
`2x=5/18`
`x=5/18:2`
`x=5/18 xx 1/2`
`x=5/2`
`@ 3/4-6x=7/13`
`6x=3/4-7/13`
`6x=11/52`
`x=11/52:6`
`x=11/52 xx 1/6`
`x=11/312`
