\(5,7:0,35=\left(-x\right):0,45\)

\(\frac{114}{7}=\left(-x\right):\frac{9}{20}\)

\(-x=\frac{114}{7}.\frac{9}{20}\)

\(-x=7\frac{23}{70}\)

\(x=-7\frac{23}{70}\)

Vậy \(x=-7\frac{23}{70}\)

Ta có: \(\frac{5,7}{0,35}=\frac{\left(-x\right)}{0,45}\)

\(\Rightarrow5,7.0,45:0,35=\left(-x\right)\)

\(\Rightarrow2,565:0,35=\left(-x\right)\)

\(\Rightarrow\left(-x\right)=7,3\left(285714\right)\)

Vậy x = -7,3 (285714)

5,7/0,35=(-x)/0,45

=>5,7x0,45=0,35x(-x)

=>0,35x(-x)=2,565

=>(-x)=2,565:0,35

=> x= 2,565: (-0,35)

=>x gần bằng 7,35

-7/23/30

Ta có :

\(\frac{5,7}{3,5}=-\frac{x}{0,45}\)

\(\Rightarrow x=\frac{5,7}{3,5}.\left(-0,45\right)\)

\(\Rightarrow x=-\frac{513}{700}\)

Vậy x = - 513 / 700

\(5,7:0,35=\left(-x\right):0,45\)

\(\Leftrightarrow-x=\frac{5,7\cdot0,45}{0,25}=10.26\)

\(\Leftrightarrow x=-10,26\)

\(\frac{5,7}{0,35}=-\frac{x}{0,45}\)

\(x=\frac{-0,45\times5,7}{0,35}\)

\(x=-\frac{513}{70}\)

a) \(\frac{x}{7}=\frac{18}{14}\)

\(\frac{x}{7}=\frac{9}{7}\)

\(\Rightarrow x=9\)

b) \(6:x=1\frac{3}{4}:5\)

\(6:x=\frac{7}{4}.\frac{1}{5}\)

\(6:x=\frac{7}{20}\)

\(x=6:\frac{7}{20}\)

\(x=\frac{120}{7}\)

vay \(x=\frac{120}{7}\)

c) \(\frac{5,7}{0,35}=\frac{-x}{0,45}\)

\(\Rightarrow-0,35x=5,7.0,45\)

\(\Rightarrow-0,35x=2,565\)

\(\Rightarrow x=\frac{-2,565}{0,35}\)

\(\Rightarrow x=\frac{-513}{70}\)

vay \(x=\frac{-513}{70}\)

a)\(\dfrac{x}{7}=\dfrac{18}{14}\)

\(\Rightarrow x=\dfrac{7.18}{14}=9\)

b)\(6:x=1\dfrac{3}{4}\)

\(\Leftrightarrow\dfrac{6}{x}=\dfrac{7}{4}\)

\(\Rightarrow x=\dfrac{6.4}{7}=\dfrac{24}{7}\)

c)5,7:0,35=(-x):0,45

\(\Leftrightarrow\dfrac{114}{7}=\dfrac{-x}{0,45}\)

\(\Rightarrow\left(-x\right)=\dfrac{114.0,45}{7}=\dfrac{-513}{70}\)

a/ \(\dfrac{x}{7}=\dfrac{18}{14}\)

\(\Leftrightarrow14x=7.18\)

\(\Leftrightarrow14x=126\)

\(\Leftrightarrow x=9\)

Vậy ....

b/ \(6:x=1\dfrac{3}{4}:5\)

\(\Leftrightarrow6:x=\dfrac{7}{20}\)

\(\Leftrightarrow x=\dfrac{120}{7}\)

Vậy ...........

bao giờ bạn cần vậy

nói đi mik giải giùm cho nha!

\(\dfrac{x}{7}=\dfrac{18}{14}\)

\(\Rightarrow x=\dfrac{18.7}{14}=9\)

Vậy x=4

Bài 1 :

a) \(\frac{x}{7}=\frac{18}{14}\)

=> x.14 = 7.18

x.14 = 126

x = 126:14

x = 9

b) \(\frac{6}{x}=\frac{7}{4}\)

=> \(x=\frac{6.4}{7}=\frac{24}{7}\)

c) Theo mình đề thế này mới đúng \(\frac{5,7}{0,35}=\frac{\left(-x\right)}{0,45}\)

=> 5,7.0,45 = 0,35.(-x)

2,565 = 0,35.(-x)

(-x) = 2,565:0,35

(-x) = 513/70

=> -x = -513/70

x = 513/70

Bài 2 : Áp dụng tính chất dãy tỉ số bằng nhau ta có :

\(\frac{x}{2}=\frac{y}{4}=\frac{z}{6}=\frac{x-y+z}{2-4+6}=\frac{8}{4}=2\)

\(\frac{x}{2}=2\) 

x = 2.2

x = 4

\(\frac{y}{4}=2\)

y = 2.4

y = 8

\(\frac{z}{6}\) = 2

z = 2.6

z = 12

Vậy x=4 ; y=8 và z=12

\(\frac{x}{7}=\frac{18}{14}\Rightarrow x=18\cdot7:17=9\)