Question

Các bạn giúp mình với a, -2/3x=4/15 b, x+1/3=2/5-(-1/3) c, -2/3x+-3/7+1/2x=-5/6 d, 2x.(x-1/7)=0

Answer 1

a, \(\frac{-2}{3}x=\frac{4}{15}\)

x = \(\frac{4}{15}:\frac{-2}{3}\)

x = \(\frac{-2}{5}\)

b, x + \(\frac{1}{3}\) = \(\frac{2}{5}-\left(\frac{-1}{3}\right)\)

x = \(\frac{11}{15}-\frac{1}{3}\)

x = \(\frac{2}{5}\)

c, \(\frac{-2}{3}\)x + \(\frac{-3}{7}\) + \(\frac{1}{2}\)x = \(\frac{-5}{6}\)

\(\frac{-1}{6}\)x + \(\frac{-3}{7}\) = \(\frac{-5}{6}\)

\(\frac{-1}{6}\)x = \(\frac{-5}{6}+\frac{3}{7}\)

\(\frac{-1}{6}\)x = \(\frac{-17}{42}\)

x = \(\frac{-17}{42}:\frac{-1}{6}\)

x = \(\frac{17}{7}\)

d, 2x(x - \(\frac{1}{7}\)) = 0

\(\Rightarrow\) 2x = 0 hoặc x - \(\frac{1}{7}\) = 0

TH1: 2x = 0

x = 0

TH2: x - \(\frac{1}{7}\) = 0

x = \(\frac{1}{7}\)

Vậy x = 0; x = \(\frac{1}{7}\)

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