Question

tìm số tự nhin x bt

a.\(x-\)\(\dfrac{5}{14}=\dfrac{3}{7}-\dfrac{1}{14}\)       b.\(\dfrac{2}{9}:x=\dfrac{1}{2}+\dfrac{2}{3}\)      c.\(\dfrac{6}{32:x}=\dfrac{12}{16}\)

Answer 1

a: =>x-5/14=6/14-1/14=5/14

=>x=10/14=5/7

b; =>2/9:x=3/6+4/6=7/6

=>x=2/9:7/6=2/9*6/7=4/21

c: =>32:x=8

=>x=4

Answer 2

a

\(x-\dfrac{5}{14}=\dfrac{3}{7}-\dfrac{1}{14}\\ x-\dfrac{5}{14}-\dfrac{3}{7}+\dfrac{1}{14}=0\\ x+\dfrac{1}{14}-\dfrac{5}{14}-\dfrac{6}{14}=0\\ x+\dfrac{1-5-6}{14}=0\\ x-\dfrac{5}{7}=0\\ x=0+\dfrac{5}{7}\\ x=\dfrac{5}{7}\)

b

\(\dfrac{2}{9}:x=\dfrac{1}{2}+\dfrac{2}{3}\\ \dfrac{2}{9}:x=\dfrac{3}{6}+\dfrac{4}{6}\\ \dfrac{2}{9}:x=\dfrac{3+4}{6}=\dfrac{7}{6}\\ x=\dfrac{2}{9}:\dfrac{7}{6}\\ x=\dfrac{2}{9}\times\dfrac{6}{7}=\dfrac{2.3.2}{3.3.7}=\dfrac{4}{21}\)

c

\(\dfrac{6}{32:x}=\dfrac{12}{16}\\ 32:x=6:\dfrac{12}{16}\\ 32:x=6\times\dfrac{16}{12}\\ 32:x=\dfrac{3\times2\times4\times4}{3\times4}\\ 32:x=8\\ x=\dfrac{32}{8}\\ x=4\)

Answer 3

`@` `\text {Answer}`

`\downarrow`

`a,`

`x - 5/14 = 3/7 - 1/14`

`x - 5/14 = 5/14`

`=> x = 5/14 + 5/14`

`=> x = 5/7`

Vậy, `x = 5/7`

`b,`

`2/9 \div x = 1/2 + 2/3`

`2/9 \div x = 7/6`

`x = 2/9 \div 7/6`

`x = 4/21`

Vậy, `x = 4/21`

`c,`

\(\dfrac{6}{32\div x}=\dfrac{12}{16}\)

`6/(32 \div x) = 3/4`

`32 \div x = 6 \div 3/4`

`32 \div x = 8`

` x = 32 \div 8`

`x = 4`

Vậy, `x = 4`

Answer 4

a. x - \(\dfrac{5}{14}=\dfrac{3}{7}-\dfrac{1}{14}\) 

=> x - \(\dfrac{5}{14}=\dfrac{5}{14}\\ \) 

=> x = \(\dfrac{5}{14}+\dfrac{5}{14}\) = \(\dfrac{5}{7}\) 

Vậy x = \(\dfrac{5}{7}\) 

b. \(\dfrac{2}{9}:x=\dfrac{1}{2}+\dfrac{2}{3}\) 

=> \(\dfrac{2}{9}:x=\dfrac{7}{6}\) 

=> x = \(\dfrac{2}{9}:\dfrac{7}{6}=\dfrac{4}{21}\) 

Vây x = \(\dfrac{4}{21}\) 

c. \(\dfrac{6}{32:x}=\dfrac{12}{16}\) 

=> \(\dfrac{6}{32:x}\) \(=\dfrac{3}{4}\) 

=> ( 32 : x) * 3 = 6 * 4 = 24

=> 32 : x = 24 : 3 = 8

=> x = 32 : 8 = 4

Vậy x = 4

Answer 5