\(a,\frac{11}{6}=-\frac{x}{5}\)

\(\Leftrightarrow-x\times6=11\times5\)

\(\Leftrightarrow-6x=55\)

\(\Leftrightarrow x=55:\left(-6\right)\)

\(\Leftrightarrow x=-\frac{55}{6}\)

\(b,4,25:8=-3,5:x\)

\(\Leftrightarrow\frac{17}{32}=--\frac{7}{2}:x\)

\(\Leftrightarrow x=-\frac{7}{2}:\frac{17}{32}\)

\(\Leftrightarrow x=-\frac{112}{17}\)

a) \(\frac{11}{6}=\frac{-x}{5}\)

\(\Rightarrow\frac{55}{30}=\frac{\left(-x\right)\cdot6}{30}\)

\(\Rightarrow55=\left(-x\right)\cdot6\)

\(\Rightarrow-x=\frac{55}{6}\)

\(\Rightarrow x=-\frac{55}{6}\)

b) \(4,25:8=-3,5:x\)

\(\Rightarrow0,53125=-3,5:x\)

\(\Rightarrow x=-3,5:0,53125\)

\(\Rightarrow x=-6,5882...\)

a) \(\dfrac{x}{4}=\dfrac{16}{128}\Rightarrow x=\dfrac{4.16}{128}=\dfrac{1}{2}=0,5\)

b)\(1\dfrac{5}{6}=\dfrac{-x}{5}\\ \Leftrightarrow\dfrac{11}{6}=\dfrac{-x}{5}\Rightarrow-x=\dfrac{5.11}{6}=\dfrac{55}{6}\Rightarrow x=-\dfrac{55}{6}\)

c) \(\dfrac{4,25}{8}=\dfrac{-3,5}{x}\Rightarrow x=\dfrac{8.\left(-3,5\right)}{4,25}=-\dfrac{112}{17}\)

a,X/4=16/28

=»x/4=4/7

=4/7.4

=7

b,1/5/6=-x/5

-x/5=11/6

X=11/6.5

X=55/6

\(a,\dfrac{x}{4}=\dfrac{16}{128}\\ \Leftrightarrow128x=4.16\\ \Leftrightarrow128x=64\\ \Leftrightarrow x=\dfrac{1}{2}\)

Vậy...

\(b,1\dfrac{5}{6}=\dfrac{-x}{5}\\ \Leftrightarrow-6x=25\\ \Leftrightarrow x=-\dfrac{25}{6}\)

Vậy...

\(c,4,25:8=-3,5:x\\ \Leftrightarrow4,25x=-3,5.8\\ \Leftrightarrow x=-28:4,25\\ \Leftrightarrow x=-\dfrac{112}{17}\)

Vậy...

Câu a :

\(\dfrac{x}{4}=\dfrac{16}{128}\) \(\Leftrightarrow x.128=4.16\) \(\Rightarrow x=\dfrac{1}{2}\)

Câu b :

\(1\dfrac{5}{6}=-\dfrac{x}{5}\) \(\Leftrightarrow11.5=-x.6\) \(\) \(\Rightarrow-x=-\dfrac{55}{6}\)

Câu c :

\(\dfrac{4,25}{8}=\dfrac{-3,5}{x}\) \(\Leftrightarrow4,25.x=8.-3,5\) \(\Rightarrow x=-\dfrac{112}{17}\)

a,Ta có : x.128=16.4

x.128=64

Suy ra : x=1/2

b,\(1\dfrac{5}{6}=\dfrac{11}{6}\)

Ta có ; 11.5=-x.6

-x.6=55

Suy ra : x=-55/6

c,Ta có : 4,25.x=-3,5.8

4,25.x=-28

Suy ra : x=-112/17

a ) x/4 = 16/128

Áp dụng tính chất phân số bằng nhau ta có 4 . 16 = x . 128 

64 = x . 128

=> x = 0,5 

b ) \(1\frac{5}{6}=\frac{-x}{5}\)

 11/6 = -x/5

Áp dụng tính chất phân số bằng nhau ta có 11 . 5 = 6 . -x

=> không tồn tại x  ( vì 11 . 5 kết quả là dương , 6 . -x sẽ có kết quả âm , dương không thể bằng âm

c ) 4,25 : 8 = -3,5 : x

    4,25 = -3.5 . 17/-14 

=> 8 = x . 17/-14

=> x = -112/17

\(a.\)

\(\dfrac{x}{4}=\dfrac{16}{128}\)

\(\Rightarrow x=\dfrac{16.4}{128}=\dfrac{1}{2}\)

\(b.\)

\(1\dfrac{5}{6}=-\dfrac{x}{5}\)

\(\Rightarrow\dfrac{11}{6}=-\dfrac{x}{5}\)

\(\Rightarrow x=\dfrac{11.\left(-5\right)}{6}=-\dfrac{55}{6}\)

\(c.\)

\(4,25:8=-3,5:x\)

\(\Rightarrow\dfrac{4,25}{8}=\dfrac{-3,5}{x}\)

\(\Rightarrow x=\dfrac{-3,5.8}{4,25}=-\dfrac{112}{17}\)

\(a)\dfrac{x}{4}=\dfrac{16}{128}\)

\(\Rightarrow\dfrac{16}{128}.4=\dfrac{1}{2}\)

\(b)1\dfrac{5}{6}=\dfrac{-x}{5}\)

\(\Rightarrow x=\dfrac{11}{6}.\left(-5\right)=\dfrac{-55}{6}\)

\(c)4,25:8=-3,5:x\)

\(\Rightarrow\dfrac{4,25}{8}=\dfrac{-3,5}{x}\)

\(\Rightarrow x=\dfrac{-3,5.8}{4,25}=\dfrac{-112}{17}\)

Chúc bạn học tốt!

a)\(\frac{x}{4}=\frac{16}{128}=\frac{1}{8}\)

\(\Rightarrow x=\frac{4}{8}=\frac{1}{2}\)

b)\(1\frac{5}{6}=\frac{11}{6}=\frac{-x}{5}\)

\(\Rightarrow x=\frac{11\times-5}{6}=\frac{-55}{6}\)

c)\(\frac{4,25}{8}=\frac{3,5}{x}\Rightarrow x=\frac{8\times3,5}{4,25}=\frac{112}{17}\)

a)\(\dfrac{x}{4}=\dfrac{16}{128}\)

\(\Leftrightarrow\dfrac{x}{4}=\dfrac{1}{8}\)

\(\Rightarrow x=\dfrac{1.4}{8}=\dfrac{1}{2}\)

b)\(1\dfrac{5}{6}=\dfrac{-x}{5}\)

\(\Leftrightarrow\dfrac{11}{6}=\dfrac{-x}{5}\)

\(\Rightarrow-x=\dfrac{11.5}{6}=\dfrac{-55}{6}\)

c)\(4,25:8=-3,5:x\)

\(\Leftrightarrow\dfrac{17}{32}=\dfrac{-3,5}{x}\)

\(\Rightarrow x=\dfrac{\left(-3,5\right).32}{17}=-\dfrac{112}{17}\)

Tìm x

a)\(\dfrac{x}{4}\)=\(\dfrac{16}{128}\)

\(\Rightarrow\)x.128=16.4

x.128=64

x=64:128

x=\(\dfrac{1}{2}\)

Vậy x=\(\dfrac{1}{2}\)

b)\(1\dfrac{5}{6}\)=\(\dfrac{-x}{5}\)

\(\dfrac{11}{6}\)=\(\dfrac{-x}{5}\)

-x:5=\(\dfrac{11}{6}\)

-x=\(\dfrac{11}{6}\).5

-x=\(\dfrac{55}{6}\)

\(\Rightarrow\)x=\(\dfrac{-55}{6}\)

Vậy x=\(\dfrac{-55}{6}\)

c)4,25:8 = -3,5:x

-3,5:x=\(\dfrac{17}{4}\)

x=-3,5:\(\dfrac{17}{4}\)

x=\(\dfrac{14}{17}\)

Vậy x=\(\dfrac{14}{17}\)