bài 1 :
a)\(\dfrac{3}{7}\) + ( -\(\dfrac{5}{2}\) ) + ( \(\dfrac{-3}{5}\) ) b) ( -\(\dfrac{4}{3}\) ) + (-\(\dfrac{2}{5}\) ) + (- \(\dfrac{3}{2}\) )
c) \(\dfrac{4}{5}\)- ( \(\dfrac{-2}{7}\) ) - ( \(\dfrac{7}{10}\) ) d ) \(\dfrac{2}{3}\) - [(-\(\dfrac{4}{7}\) ) - ( \(\dfrac{1}{2}\) + \(\dfrac{3}{8}\) )]
bài 2 : tìm x , biêt
a) x + \(\dfrac{1}{3}\) = \(\dfrac{3}{4}\) ; b) x- \(\dfrac{2}{5}\) = \(\dfrac{5}{7}\)
c) -x - \(\dfrac{2}{3}\) = - \(\dfrac{6}{7}\) d) \(\dfrac{4}{7}\) -x = \(\dfrac{1}{3}\)
( mai nộp bài rôi ai giúp vs )
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