cái gì đấy lỗi à

lỗi

Lỗi rồi nha! -_-

\(1,\frac{2}{3}+\frac{4}{9}+\frac{1}{5}+\frac{2}{15}+\frac{3}{2}-\frac{17}{18}\)

\(< =>\frac{4}{9}+\frac{3}{2}+\left(\frac{2}{3}+\frac{1}{5}+\frac{2}{15}\right)-\frac{17}{18}\)

\(< =>\frac{8}{18}+\frac{27}{18}+\left(\frac{10}{15}+\frac{3}{15}+\frac{2}{15}\right)-\frac{17}{18}\)

\(< =>\frac{35}{18}+1-\frac{17}{18}\)

\(< =>\frac{53}{18}-\frac{17}{18}\)

\(< =>2\)

\(2,\frac{13}{28}\cdot\frac{5}{12}-\frac{5}{28}\cdot\frac{1}{12}\)

\(< =>\left(\frac{13}{28}-\frac{5}{28}\right)\cdot\left(\frac{5}{12}-\frac{1}{12}\right)\)

\(< =>\frac{2}{7}\cdot\frac{1}{3}\)

\(< =>\frac{2}{21}\)

\(3,\frac{19}{4}\cdot\frac{15}{23}-\frac{15}{4}\cdot\frac{7}{23}+\frac{15}{4}\cdot\frac{11}{23}\)

\(< =>\frac{285}{92}-\frac{105}{92}+\frac{165}{92}\)

\(< =>\frac{15}{4}\)

cảm ơn bạn nha bạn chắc chăn đúng không

bạn viết dấu gạch ngang của phân số như thế nào đấy nguyen thi hien

j HGBYH B

/ là phân số nha

11/13-(5/42-x)=(15/28-11/13)

11/13-(5/42-x)=-37/182

(5/42-x)=11/13+37/182

(5/42-x)=191/182

x=5/42-191/182

x=-254/273

vậy x=-254/273

bạn ấn vào chữ M nằm ngang ở dưới câu hỏi khi bạn trả lời là sẽ ấn được phân số nhé 

còn gửi câu trả lời cũng tương tự 

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

\(< =>x+\frac{1}{3}=\frac{2}{5}+\frac{1}{3}\)

\(< =>x=\frac{1}{3}-\frac{1}{3}+\frac{2}{5}=\frac{2}{5}\)

\(c,\frac{2}{3}x+\frac{5}{7}=\frac{3}{10}\)

\(< =>\frac{2}{3}x=\frac{3}{10}-\frac{5}{7}=-\frac{29}{70}\)

\(< =>x=\frac{-29}{70}:\frac{2}{3}=-\frac{7}{140}\)

\(d,\frac{3}{7}-x=\frac{1}{4}-\left(-\frac{3}{5}\right)\)

\(< =>\frac{3}{7}-\frac{1}{4}-\frac{3}{5}=x\)

\(< =>x=-\frac{59}{140}\)

\(e,-\frac{21}{12}x+\frac{1}{3}=-\frac{2}{3}\)

\(< =>-\frac{21}{12}x=-\frac{2}{3}-\frac{1}{3}=-1\)

\(< =>x=\frac{12}{21}\)

a) Ta có : ( x + 1 ).( 3 - x ) > 0

Th1 : \(\hept{\begin{cases}x+1>0\\3-x>0\end{cases}\Rightarrow\hept{\begin{cases}x>-1\\x>3\end{cases}\Rightarrow}x>3}\)

Th2 : \(\hept{\begin{cases}x+1< 0\\3-x< 0\end{cases}\Rightarrow\hept{\begin{cases}x< -1\\x< 3\end{cases}\Rightarrow}x< -1}\)

sao ko ai làm giúp mk vậy

a.-1,75-(-\(\dfrac{1}{9}\)-2\(\dfrac{1}{8}\))
-1,75-\(\dfrac{1}{9}+\dfrac{17}{8}\)
\(-\dfrac{7}{4}-\dfrac{1}{9}+\dfrac{17}{8}\)
\(\dfrac{-126}{72}-\dfrac{8}{72}+\dfrac{153}{72}\)
=\(\dfrac{19}{72}\)

b.\(\dfrac{-1}{12}-\left(2\dfrac{5}{8}-\dfrac{1}{3}\right)\)
\(\dfrac{-1}{12}-\left(\dfrac{21}{8}-\dfrac{1}{3}\right)\)
\(\dfrac{-1}{12}-\dfrac{21}{8}+\dfrac{1}{3}\)
\(\dfrac{-2}{24}-\dfrac{63}{24}+\dfrac{64}{24}\)
=\(\dfrac{-1}{24}\)

\(\dfrac{-5}{6}-\left(\dfrac{-3}{8}+\dfrac{1}{10}\right)\)
\(\dfrac{-5}{6}-\dfrac{-3}{8}-\dfrac{1}{10}\)
 

a,   11/13 - ( 5/42 - x ) = - (5/28 - 11/13)

    11/13 - (5/42 - x) = - 5/28 + 11/13

    - (5/42 - x) + 5/28 = -11/13 + 11/13

 - 5/42 + x + 5/28 = 0

- 5/42 + x = 0 - 5/28

- 5/42 + x = - 5/28

x = -5/28 +5/42

x = - 5/84

b, / x + 4/15 \ - / - 3,75 \ = - / - 2,15 \

./ x + 4/15 \ - 3,75 = - 2,15

/ x + 4/15 \ = -2,15 + 3,75

/ x + 4/15 \ = 1,6

x + 4 / 15 = 1,6                      hoặc x+ 4/15 = - 1,6

x = 1,6 - 4/15                                   x = - 1,6 -4/15

x = 4/3                                              x = -28/15

Vậy x = 4/3 hoặc x = - 28/15

c, ( 0,25 - 30% x ) . 1/3 = 1/4 - 31/6

( 1/4 - 3/10 x ) . 1/3 = - 59/12

( 1/4 - 3/10 x ) = - 59/12 : 1/3

1/4 - 3/10 x = - 59/4

3/10 x = 1/4 + 59/4

3/10 x = 15

x = 15 : 3/10

x = 50

d, ( x - 1/2 ) : 1/3 + 5/7 = 68/7

( x - 1/2 ) : 1/3 = 68/7 - 5/7

( x - 1/2 ) : 1/3 = 63/7

( x - 1/2 ) = 63/7 . 1/3

x -1/2 = 3 

x = 3 + 1/2

x = 7/2

1) Ta có: \(\left(\dfrac{3}{4}\cdot\dfrac{5}{97}+\dfrac{1}{9}\cdot\dfrac{13}{47}\right)\cdot\left(\dfrac{1}{5}-\dfrac{7}{25}\cdot\dfrac{5}{7}\right)\)

\(=\left(\dfrac{3}{4}\cdot\dfrac{5}{97}+\dfrac{1}{9}\cdot\dfrac{13}{47}\right)\cdot\left(\dfrac{1}{5}-\dfrac{1}{5}\right)\)

=0

2) Ta có: \(\dfrac{8}{17}\cdot\dfrac{4}{15}+\dfrac{8}{17}\cdot\dfrac{22}{15}-\dfrac{8}{15}\cdot\dfrac{9}{17}\)

\(=\dfrac{8}{17}\left(\dfrac{4}{15}+\dfrac{22}{15}-\dfrac{9}{15}\right)\)

\(=\dfrac{8}{17}\cdot\dfrac{15}{15}=\dfrac{8}{17}\)

3) Ta có: \(\dfrac{2021}{2}\cdot\dfrac{1}{3}+\dfrac{4042}{4}\cdot\dfrac{1}{5}+\dfrac{6063}{3}\cdot\dfrac{22}{15}\)

\(=\dfrac{2021}{2}\left(\dfrac{1}{3}+\dfrac{1}{5}\right)+2021\cdot\dfrac{22}{15}\)

\(=\dfrac{2021}{2}\cdot\dfrac{8}{15}+\dfrac{2021}{2}\cdot\dfrac{44}{15}\)

\(=\dfrac{2021}{2}\cdot\dfrac{52}{15}\)

\(=\dfrac{52546}{15}\)

4) Ta có: \(\dfrac{4}{7}\cdot\dfrac{2}{13}+\dfrac{8}{13}:\dfrac{7}{4}+\dfrac{4}{7}:\dfrac{13}{2}+\dfrac{4}{7}\cdot\dfrac{1}{13}\)

\(=\dfrac{4}{7}\left(\dfrac{2}{13}+\dfrac{8}{13}+\dfrac{2}{13}+\dfrac{1}{13}\right)\)

\(=\dfrac{4}{7}\)

1) Tính biểu thức:

a)\(x+\frac{15}{16}+\frac{7}{8}=\frac{15}{4}\)

\(x+\frac{29}{16}=\frac{15}{4}\)

\(x=\frac{15}{4}-\frac{29}{16}\)

\(x=\frac{31}{16}\)

b)\(x-\frac{27}{28}-\frac{9}{14}=\frac{13}{7}\)

\(x-\frac{45}{28}=\frac{13}{7}\)

\(x=\frac{13}{7}+\frac{45}{28}\)

\(x=\frac{97}{28}\)

c)\(x\times\frac{1}{5}+x+\frac{1}{6}=\frac{2}{3}\)

\(x\times\frac{1}{5}+x=\frac{2}{3}-\frac{1}{6}\)

\(x\times\left(\frac{1}{5}+1\right)=\frac{1}{2}\)

\(x\times\frac{6}{5}=\frac{1}{2}\)

\(x=\frac{1}{2}:\frac{6}{5}\)

\(x=\frac{5}{12}\)

d)\(x:14=\frac{1}{4}+\frac{2}{9}+\frac{3}{4}\)

\(x:14=\frac{11}{9}\)

\(x=\frac{11}{9}\times14\)

\(x=\frac{154}{9}\)

#H