Question

Tìm x, biết:

a) \(\dfrac{-3}{7}+x=\dfrac{1}{3}\)

b) \(\dfrac{3}{4}+\dfrac{1}{4}:x=\dfrac{2}{5}\)

c) \(1\dfrac{1}{3}:0,8=\dfrac{2}{3}:0,1x\)

d) \(\left|x-3\right|=\dfrac{1}{2}\)

Answer 1

b) \(\dfrac{3}{4}+\dfrac{1}{4}:x=\dfrac{2}{5}\)

\(\dfrac{1}{4}:x=\dfrac{2}{5}-\dfrac{3}{4}\)

\(\dfrac{1}{4}:x=\dfrac{7}{20}\)

\(x=\dfrac{1}{4}:\dfrac{7}{20}=\dfrac{5}{7}\)

Answer 2

\(\left|x-3\right|=\dfrac{1}{2}\)

\(x-3=\pm\dfrac{1}{2}\)

x-3	\(\dfrac{1}{2}\)	\(-\dfrac{1}{2}\)
x	\(3\dfrac{1}{2}\)	\(2\dfrac{1}{2}\)

Answer 3

c) \(1\dfrac{1}{3}:0,8=\dfrac{2}{3}:0,1x\)

\(\dfrac{5}{3}=\dfrac{2}{3}:0,1x\)

\(0,1x=\dfrac{2}{3}:\dfrac{5}{3}\)

\(0,1x=0,4\)

\(x=0,4:0,1=4\)

Answer 4

a) \(\dfrac{-3}{7}+x=\dfrac{1}{3}\)

\(x=\dfrac{1}{3}-\dfrac{-3}{7}\)

\(x=\dfrac{16}{21}\)