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Question

giải bài 9 (trong SGK ) nhé

ai nhanh nhất được lik e

Lyzimi · Accepted Answer

a) x + $\frac{1}{3} = \frac{3}{4}$ => x = $\frac{3}{4} - \frac{1}{3} = \frac{9}{12} - \frac{4}{12} = \frac{5}{12}$

b) x - $\frac{2}{5} = \frac{5}{7}$ => x = $\frac{5}{7} + \frac{2}{5} = \frac{25}{35} + \frac{14}{35}= \frac{39}{35} = 1\frac{4}{35}$

c) -x - $\frac{2}{3}$ = $- \frac{6}{7}$ => $\frac{-2}{3} + \frac{6}{7} = x => x = -\frac{14}{21} + \frac{18}{21} = \frac{4}{21}$

d) $\frac{4}{7} - x = \frac{1}{3}$ => $\frac{4}{7} - \frac{1}{3} = x => x = \frac{12}{21} - \frac{7}{21} = \frac{5}{21}$

Câu trả lời:

a) x + $\frac{1}{3} = \frac{3}{4}$ => x = $\frac{3}{4} - \frac{1}{3} = \frac{9}{12} - \frac{4}{12} = \frac{5}{12}$

b) x - $\frac{2}{5} = \frac{5}{7}$ => x = $\frac{5}{7} + \frac{2}{5} = \frac{25}{35} + \frac{14}{35}= \frac{39}{35} = 1\frac{4}{35}$

c) -x - $\frac{2}{3}$ = $- \frac{6}{7}$ => $\frac{-2}{3} + \frac{6}{7} = x => x = -\frac{14}{21} + \frac{18}{21} = \frac{4}{21}$

d) $\frac{4}{7} - x = \frac{1}{3}$ => $\frac{4}{7} - \frac{1}{3} = x => x = \frac{12}{21} - \frac{7}{21} = \frac{5}{21}$