a: \(\left|x-7\right|+13=25\)

=>|x-7|=12

=>x-7=12 hoặc x-7=-12

=>x=19 hoặc x=-5

b: 26-|x+9|=-13

=>|x+9|=39

=>x+9=39 hoặc x+9=-39

=>x=30 hoặc x=-48

`5 4/7:x-26=13`

`39/7:x=13+26`

`39/7:x=39`

`x=39/7:39`

`x=1/7`

Vậy `x=1/7`

cảm ơn nhanh kết bn fakeoob nói  chuyện

\(\frac{5}{14}\times\frac{7}{13}\times\frac{26}{25}=\frac{5\times7\times26}{14\times13\times25}=\frac{5\times7\times13\times2}{7\times2\times13\times5\times5}=\frac{1}{5}\)

\(\dfrac{5}{14}\times\dfrac{7}{13}\times\dfrac{26}{25}=\dfrac{35}{182}\times\dfrac{26}{25}=\dfrac{5}{26}\times\dfrac{26}{25}=\dfrac{130}{650}=\dfrac{1}{5}\)

\(\dfrac{5}{14}\) x \(\dfrac{7}{13}\) x \(\dfrac{26}{25}\)

=\(\dfrac{5}{26}\) x \(\dfrac{26}{25}\)

=\(\dfrac{1}{5}\)

a. 123 x 456 = 56088

b. 26 x 7 + 13 x 26

= 26 x ( 7 + 13 )

= 26 x 20

= 520

c. 1301 x 20028 = 26 056 428

Ok

tớ nhìn nhầm

Xin lỗi nhé

\(\frac{21}{13}\cdot x=-\frac{7}{26}\)

\(\Leftrightarrow x=-\frac{1}{6}\)

vậy..........

bằng con chó đấy

\(x+\dfrac{1}{3}=-\dfrac{7}{12}\\ \Rightarrow x=-\dfrac{7}{12}-\dfrac{1}{3}=-\dfrac{7}{12}-\dfrac{4}{12}=-\dfrac{11}{12}\)

\(x+\dfrac{1}{3}=\dfrac{7}{26}.\dfrac{-13}{6}\)

\(x+\dfrac{1}{3}=\dfrac{-91}{156}\)

\(x+\dfrac{1}{3}=\dfrac{-7}{13}\)

\(x=\dfrac{-11}{12}\)

a) \(13.\left(7-x\right)=26\)

\(7-x=26:13\)
\(7-x=2\)
\(x=7-2\)
\(x=5\)

b() \(5.\left(x-9\right)=15\)
\(x-9=15:5\)
\(x-9=3\)
\(x=3+9\)
\(x=12\)

\(13X\left(7-x\right)=16\)

\(=>7-x=\frac{16}{13}\)

\(=>x=7-\frac{16}{13}\)

\(=>x=\frac{75}{13}\)

\(5X\left(x-9\right)=15\)

\(=>x-9=3\)

\(=>x=9+3\)

\(=>x=12\)