(\(\frac{5}{7}-y\)) x \(\frac{14}{5}=\frac{6}{5}\)

\(\frac{5}{7}-y\)            = \(\frac{6}{5}:\frac{14}{5}\)

\(\frac{5}{7}-y\)             = \(\frac{3}{7}\)

            y                 = \(\frac{5}{7}-\frac{3}{7}\)

           y                  = \(\frac{2}{7}\)

\(\left(\frac{5}{7}-y\right)\cdot\frac{14}{5}=\frac{7}{10}+\frac{1}{2}\)

\(\Leftrightarrow\left(\frac{5}{7}-y\right)\cdot\frac{14}{5}=\frac{7}{10}+\frac{5}{10}\)

\(\Leftrightarrow\left(\frac{5}{7}-y\right)\cdot\frac{14}{5}=\frac{6}{5}\)

\(\Leftrightarrow\frac{5}{7}-y=\frac{6}{5}\div\frac{14}{5}\)

\(\Leftrightarrow\frac{5}{7}-y=\frac{3}{7}\)

\(\Rightarrow y=\frac{5}{7}-\frac{3}{7}=\frac{2}{7}\)

Nên tự tính 

Nếu thik thì lấy máy tính tính cho nhanh nha bạn

a) y = 5/14 : 6/7

y = 5/12 

vậy y = 5/12

b) y = 4/9 x 2/3 

y = 8/27 

vậy t = 8/27

c) y = 1/2 - 3/10 

y = 1/5

vậy y = 1/5

d) y = 5/6 - 1/3

y = 1/2

vậy y = 1/2

\(\left(\frac{5}{7}:y\right)\cdot\frac{14}{5}=\frac{7}{10}+\frac{1}{2}\)

\(\frac{5}{7}:y\cdot\frac{14}{5}=\frac{7}{10}+\frac{5}{10}\)

\(\frac{5}{7}\cdot\frac{14}{5}:y=\frac{12}{10}\)

\(2:y=\frac{12}{10}\)

\(y=2:\frac{12}{10}\)

\(y=2\cdot\frac{10}{12}\)

\(y=\frac{5}{3}\)

Câu này trong Violympic chứ gì !? Mình đọc lại đề bài thì thấy sai, mình sửa lại thành: Tìm y biết \(\left(\frac{5}{7}-y\right)\times\frac{14}{5}=\frac{7}{10}+\frac{1}{2}\)

\(\left(\frac{5}{7}-y\right)\times\frac{14}{5}=\frac{7}{10}+\frac{5}{10}\)

\(\left(\frac{5}{7}-y\right)\times\frac{14}{5}=\frac{12}{10}\)

\(\frac{5}{7}-y=\frac{12}{10}:\frac{14}{5}\)

\(\frac{5}{7}-y=\frac{3}{7}\)

\(y=\frac{5}{7}-\frac{3}{7}\)

\(y=\frac{2}{7}\)

Bạn Mai Thanh Xuân sai rồi nha

(5/7:y)*14/5=7/10+1/2

(5/7:y)*14/5=6/5

5/7:y=6/5:14/5

5/7:y=3/7

y=5/7:3/7

y=5/3

Vậy y=5/3

cho mik đi r mik giúp cho

a.

x/y x 3/4 = 5/6 + 1/3

x/y x 3/4 = 7/6

        x/y = 7/6 : 3/4 

        x/y = 14/9

b.

7/9 : x/y = 10/7 - 13/14

7/9 : x/y = 1/2

        x/y = 7/9 : 1/2

        x/y = 14/9

cho 1 k nha bn

X/y = 14/9

Nha 

Ht 

\(\left(\frac{5}{7}-y\right)x\frac{14}{5}=\frac{7}{10}+\frac{1}{2}\)

\(\left(\frac{5}{7}-y\right)x\frac{14}{5}=\frac{6}{5}\)

\(\frac{5}{7}-y=\frac{6}{5}:\frac{14}{5}\)

\(\frac{5}{7}-y=\frac{3}{7}\)

Y = \(\frac{5}{7}-\frac{3}{7}\)

Y = \(\frac{2}{7}\)

\(\left(\frac{5}{7}-y\right).\frac{14}{5}=\frac{7}{10}+\frac{1}{2}\)

\(\left(\frac{5}{7}-y\right).\frac{14}{5}=\frac{6}{5}\)

\(\frac{5}{7}-y=\frac{6}{5}\div\frac{14}{5}\)

\(\frac{5}{7}-y=\frac{3}{7}\)

\(y=\frac{5}{7}-\frac{3}{7}\)

\(y=\frac{2}{7}\)

\(\left(\frac{5}{7}-y\right)\) x \(\frac{14}{5}=\frac{7}{10}+\frac{1}{2}\)

\(\left(\frac{5}{7}-y\right)\) x \(\frac{14}{5}=\frac{6}{5}\)

\(\frac{5}{7}-y\)  = \(\frac{6}{5}:\frac{14}{5}\)

\(\frac{5}{7}-y\) = \(\frac{3}{7}\)

y= \(\frac{2}{7}\)

có ai giúp tôi ko?

a)y:0,01=285:10

=>y=\(\frac{285:10}{0,01}\)=2850

b)\(\frac{1}{4}\times y=3-\frac{2}{5}\)

=>\(\frac{1}{4}\times y=\frac{13}{5}\)

=>y=\(\frac{13}{5}:\frac{1}{4}=\frac{13}{5}\times4=\frac{52}{5}\)

c)\(\frac{7}{3}:y=\frac{14}{15}\)

=>\(y=\frac{7}{3}:\frac{14}{15}=\frac{7}{3}\times\frac{14}{15}\)

=>y=\(\frac{98}{45}\)

(5/7-y)x14/5=6/5

5/7-y=6/5:14/5

5/7-y=3/7

y=5/7-3/7

x=2/7

Ta có : \(\left(\frac{5}{7}-y\right)\times\frac{14}{5}=\frac{7}{10}+\frac{1}{2}\)

\(\Rightarrow\left(\frac{5}{7}-y\right)\times\frac{14}{5}=\frac{12}{10}=\frac{6}{5}\)

\(\Rightarrow\left(\frac{5}{7}-y\right)=\frac{6}{5}:\frac{14}{5}\)

\(\Rightarrow\left(\frac{5}{7}-y\right)=\frac{30}{70}=\frac{3}{7}\)

\(y=\frac{5}{7}-\frac{3}{7}=\frac{2}{7}\)

theo mình là 2/7

a)100-9:(372:3.y-1)-14=83

<=>100-9:(124y-1)-14=83

<=>86-9:(124y-1)=83

<=>9:(124y-1)=3

<=>124y-1=3

<=>124y=4

<=>y=\(\frac{1}{31}\approx0,3223\)

b)7260-120:24.y+924=528,3

<=>8184-5y=528,3

<=>5y=7655,7

<=>y=1531,14

c)2000-52:(615:3:y-15)-14=1984

<=>1986-52:(205:y-15)=1984

<=>52:(205:y-15)=2

<=>205:y-15=26

<=>205:y=41

<=>y=5

d)y+y.1/3+5/18=7/18

<=>4/3y=1/9

<=>y=1/12

e)13/15-(5/21+y)7/12=7/10

<=>7/12.(5/21+y)=1/6

<=>5/36+7/12y=1/6

<=>7/12y=1/36

<=>y=1/21\(\approx\)0,4762

h)y+2.y+3.y+...+10.y=49,5

<=>55y=49,5

<=>y=0,9

i)y.(1975/8.9+1885/9.10+1755/10.11+1579/11.12)=1/24

<=>7991,364899y=1/24

<=>y=33/6329161

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