Yx,2-3,45=4,68

Yx1,2=4,68+3,45

Yx1,2=8,13

Y=8,13:1,2

Y=6,775

x.1,2-3,45=4,68

x.1,2=4,68+3,45

x.1,2=8,13

x=8,13:1,2

x=6,775

= 3,45 x (123 + 4 - 27)

= 3,45 x 100

= 345

HT

345

34500

\(x-3,45=\frac{90,5}{15}=\frac{181}{30}\)

=> \(x=\frac{181}{30}+3,45=\frac{569}{60}\)

x - 3 . 45 = 90 . 5 : 15

x -   135  = 450 : 15

x - 135 = 30

        x = 30 + 135

        x = 165

Vậy x = 165

x - 4,68 = 10,5

x          = 10,5 + 4,68

x          = 15,18

x-4,68=10,5

x=10,5+4,68

x+15,18

x-4.68=10.5

x-272=50

x=50+272

x=322

đề k rõ j hết phải là zầy k p :

X * 1,2 - 3.45=4.68

==> x=6,775

3,45 x 9 + 3,45 = 3,45 x 10 

                          = 34,5

Ta có : 3, 45 x 9 + 3, 45

       = 3, 45 x ( 9 + 1 )

       = 3, 45 x 10

       = 34, 5

(3.45 x 9) +3.45 = 34,5

\(\left(\dfrac{1}{1.2}+\dfrac{1}{2.3}+\dfrac{1}{3.4}+...+\dfrac{1}{8.9}+\dfrac{1}{9.10}\right).100-\left[\dfrac{5}{2}:\left(x+\dfrac{206}{100}\right)\right]:\dfrac{1}{2}=89\)

\(\Rightarrow\left(1-\dfrac{1}{2}+\dfrac{1}{2}-\dfrac{1}{3}+\dfrac{1}{3}-\dfrac{1}{4}+...+\dfrac{1}{8}-\dfrac{1}{9}+\dfrac{1}{9}-\dfrac{1}{10}\right).100-\left[\dfrac{5}{2}:\left(x+\dfrac{206}{100}\right)\right]:\dfrac{1}{2}=89\)

\(\Rightarrow\left(1-\dfrac{1}{10}\right).100-\left[\dfrac{5}{2}:\left(x+\dfrac{206}{100}\right)\right]:\dfrac{1}{2}=89\)

\(\Rightarrow\left(100-10\right)-\left[\dfrac{5}{2}:\left(x+\dfrac{206}{100}\right)\right]:\dfrac{1}{2}=89\)

\(\Rightarrow90-\left[\dfrac{5}{2}:\left(x+\dfrac{206}{100}\right)\right]:\dfrac{1}{2}=89\)

\(\Rightarrow\left[\dfrac{5}{2}:\left(x+\dfrac{206}{100}\right)\right]:\dfrac{1}{2}=1\)

\(\Rightarrow\dfrac{5}{2}:\left(x+\dfrac{206}{100}\right)=1.2=2\)

\(\Rightarrow\left(x+\dfrac{206}{100}\right)=\dfrac{5}{2}:2=\dfrac{5}{2}.\dfrac{1}{2}=\dfrac{5}{4}\)

\(\Rightarrow x=\dfrac{5}{4}-\dfrac{206}{100}=\dfrac{125}{100}-\dfrac{206}{100}\)

\(\Rightarrow x=-\dfrac{81}{100}\)