Question

Bài 1 : Tìm x:

a)\(\dfrac{62}{7}x=\dfrac{29}{9}:\dfrac{3}{56}\)

b) \(\dfrac{1}{5}:x=\dfrac{1}{5}+\dfrac{1}{7}\)

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

d)\(\dfrac{1}{2}\) : x = 2 (a\(\in\) z) a+1

Answer 1

a: \(\Leftrightarrow x\cdot\dfrac{62}{7}=\dfrac{29}{9}\cdot\dfrac{56}{3}=\dfrac{1624}{27}\)

hay \(x=\dfrac{1624}{27}:\dfrac{62}{7}=\dfrac{5684}{837}\)

b: \(\Leftrightarrow\dfrac{1}{5}:x=\dfrac{12}{35}\)

nên \(x=\dfrac{1}{5}:\dfrac{12}{35}=\dfrac{1}{5}\cdot\dfrac{35}{12}=\dfrac{7}{12}\)

c: \(\Leftrightarrow\left|2x+\dfrac{1}{3}\right|=\dfrac{30-7}{42}=\dfrac{23}{42}\)

=>2x+1/3=23/42 hoặc 2x+1/3=-23/42

=>2x=3/14 hoặc 2x=-37/42

=>x=3/28 hoặc x=-37/84