\(a,y\times2,8+5,2\times y=48\\ y\times\left(2,8+5,2\right)=48\\ y\times8=48\\ y=\dfrac{48}{8}=6\\ ---\\ b,y\times12,25-y+y\times2,75=1050\\ y\times\left(12,25-1+2,75\right)=1050\\ y\times14=1050\\ y=\dfrac{1050}{14}=75\)

a: \(y\cdot2,8+y\cdot5,2=48\)

=>\(y\left(2,8+5,2\right)=48\)

=>\(8y=48\)

=>\(y=\dfrac{48}{8}=6\)

b: \(y\cdot12,25-y+y\cdot2,75=1050\)

=>\(y\left(12,25-1+2,75\right)=1050\)

=>\(y\cdot14=1050\)

=>\(y=\dfrac{1050}{14}=75\)

\(4,6\times y+y+4,4\times y=2017\)

\(y\text{​​​}\times\text{​​}\left(4,6+1+4,4\right)=2017\)

\(y\text{ }\times10=2017\)

\(y\text{ }=2017:10=201,7\)

4,6 x y + y +4,4 x y = 2017

=> (4,6+4,4)*y=2017

=. 9*y=2017

=> y= \(\frac{2017}{9}\)

y*(4,6+1+4,4)=2017

y*10=2017

y=2017:10

y=201,7

/2,8-x/+1,2=/-4,6/

/2,8-x/       =4,6- 1,2

/2,8-x/       =3,4

=> 2,8-x=3,4 hoặc 2,8-x=-3,4

=> x=-0,6      hoặc  x=6,2

`y xx 3,2 + 6,8 xx y = 68,84 + 4,6`

`y xx ( 3,2 + 6,8 ) = 73,44`

`y xx 10 = 73,44`

`y = 73,44 : 10`

`y = 7,344`

y x (3,2 + 6,8) = 73,44

y x 10 = 73,44

y = 73,44 : 10

y = 7,344

y x 3,2+6,8 x y= 68,84+4,6

=> y x (3,2+6,8)=73,44

=>y x 10=73,44

=> y= 7,344

Chúc bạn học tốt!

1) x.(y - 2) + (y - 2) = 6

=> (x + 1)(y - 2) = 6 = 1 . 6 = 6. 1 = -1 . (-6) = -6 . (-1) = 2 . 3 = 3 . 2 = -2 . (-3) = (-3) . (-2)

Lập bảng :

Vậy ...

1, x.(y+1)+2.(y+1)=7

   (x+2).(y+1)=7

    Ta có bảng

 Vậy ...

4,6 x y + 6,4 x y = 0,32

=>y x (4,6 + 6,4 )= 0,32

=>y x 11=0.32

=>y=0.32:11

=>y=8/275

xem trên mạng nhé 

\(A=0,36.350+0,9.45.4+3.20.12\)
\(A=0,36.350+0,36.45+3,6.20\)
\(A=0,36.350+0,36.45+0,36.10.20\)
\(=0,36.\left(350+45+20.10\right)\)
\(A=0,36.595\)
\(A=214,2\)

\(b.12,8.3,2-y:4,6=35,06\)
\(40,96-y:4,6=35,06\)
\(y:4,6=40,96-35,06\)
\(y:4,6=5,9\)
\(y=5,9.4,6\)
\(y=27,14\)

\(y+y.\frac{3}{2}\)\(+y:\frac{2}{7}\)\(=21\)
\(y.1+y.\frac{3}{2}\)\(+y.\frac{7}{2}\)\(=21\)
\(y(1+\frac{3}{2}+\frac{7}{2}\)\()=21\)
\(y.6=21\)
\(y=\frac{21}{6}\)