Question

1. Tìm x biết:

a. ( 4.5 - 2x ) . ( -1\(\frac{4}{7}\)) = \(\frac{11}{14}\)

b. ( 3\(\frac{1}{2}\) - 2x ) . (-3\(\frac{1}{3}\)) = 7\(\frac{1}{3}\)

c. \(\frac{4}{9}\). x =\(\frac{9}{8}\) - 0.125

d.\(\frac{1}{2}\). x + \(\frac{3}{5}\). ( x-2 ) = 3

Answer 1

Giải:

a) \(\left(4,5-2x\right).\left(-1\dfrac{4}{7}\right)=\dfrac{11}{14}\)

\(\Leftrightarrow\left(4,5-2x\right).\left(-\dfrac{3}{7}\right)=\dfrac{11}{14}\)

\(\Leftrightarrow4,5-2x=\dfrac{11}{14}:\left(-\dfrac{3}{7}\right)=-\dfrac{11}{6}\)

\(\Leftrightarrow2x=4,5-\left(-\dfrac{11}{6}\right)\)

\(\Leftrightarrow2x=\dfrac{19}{3}\)

\(\Leftrightarrow x=\dfrac{19}{3}:2=\dfrac{19}{6}\)

Vậy ...

b) \(\dfrac{4}{9}x=\dfrac{9}{8}-0,125\)

\(\Leftrightarrow\dfrac{4}{9}x=\dfrac{9}{8}-\dfrac{1}{8}\)

\(\Leftrightarrow\dfrac{4}{9}x=1\)

\(\Leftrightarrow x=1:\dfrac{4}{9}=\dfrac{9}{4}\)

Vậy ...

Các câu còn lại làm tương tự.