Bài 1: 

a: x/-2=-18/x

=>x²=36

=>x=6 hoặc x=-6

b: x/2+x/5=17/10

=>7/10x=17/10

hay x=17/7

`x xx 6/7=5/14`

`=>x=5/14:6/7`

`=>x=5/14xx7/6`

`=>x=35/84`

`=>x=5/12`

Vậy `x=5/12`

__

`x:2/3=4/9`

`=>x=4/9xx2/3`

`=>x=8/27`

Vậy `x=8/27`

__

`x-1/4=3/2`

`=>x=3/2+1/4`

`=>x=6/4+1/4`

`=>x=7/4`

Vậy `x=7/4`

__

`x+4/5=8/9`

`=>x=8/9-4/5`

`=>x=40/45-36/45`

`=>x=4/45`

Vậy `x=4/45`

\(x\cdot\dfrac{6}{7}=\dfrac{5}{14}\)

\(x\)         \(=\dfrac{5}{14}:\dfrac{6}{7}\)

\(x\)           \(=\dfrac{5}{12}\)

\(x:\dfrac{2}{3}=\dfrac{4}{9}\)

\(x\)        \(=\dfrac{4}{9}\cdot\dfrac{2}{3}\)

\(x\)          \(=\dfrac{8}{27}\)

\(x-\dfrac{1}{4}=\dfrac{3}{2}\)

\(x\)          \(=\dfrac{3}{2}+\dfrac{1}{4}\)

\(x\)            \(=\dfrac{7}{4}\)

\(x+\dfrac{4}{5}=\dfrac{8}{9}\)

\(x\)          \(=\dfrac{8}{9}-\dfrac{4}{5}\)

\(x\)            \(=\dfrac{4}{45}\)

Tớ chưa học đến

ai lm nhanh tui tick cho

chỉ 2 bn đầu tiên lm xong

Bài 1: số ?

1 giờ 32 =........92.......phút

276 phút = ..........4....giờ ..36.....phút

9732 kg =....9.......tấn ......732......kg

7102 cm =..710....dm....2...cm

bài 2 tìm x

x+3/4=5/6:1/2

x + 3/4 = 5/3

x = 5/3 - 3/4

x = 11/12

bài 3 : tính nhanh 

  3/5 nhân 7/9 -3/5 nhân 2/9

3/5 x ( 7/9 - 2/9)

= 3/5 x 5/9

= 1/3

\(x+x\cdot3:\dfrac{2}{9}+x:\dfrac{2}{7}=252\)

\(\Leftrightarrow x+x\cdot3\cdot\dfrac{9}{2}+x\cdot\dfrac{7}{2}=252\)

\(\Leftrightarrow x\cdot18=252\)

hay x=14

X- 9 = 21:5 

X- 9 = 4,2

x = 4,2 + 9

x = 13,2

X : 3 = 1,248 : 4

X : 3 = 0,312

x = 0,312 x 3

x = 0,936

x - 9 = 4,2

x = 4,2 + 9 =13,2

x : 3 = 0,312

x = 0,312 x 3 = 0,936

GIÚP MÌNH NHANH VỚI MỌI NGƯỜI ƠI 

a, 3/4 + 1/4.x=2

    1/4.x        = 2-3/4

     1/4.x      =5/4

     x           = 5/4:1/4

     x           = 5

b, x-2/3.9/4=2,5-1/2

    x-2/3.9/4=2

    x-2/3     =2:9/4

    x-2/3   =8/9

     x        = 8/9+2/3

     x         = 14/9

c, 2.x+1/3=4/3

    2.x      =4/3-1/3

    2.x      =1

       x      =11:2

       x      = 1/2

a, 5/252

b, 11/90

a)\(=>x=\dfrac{5}{9}:\dfrac{4}{7}=\dfrac{35}{36}\)

b)\(=>x=\dfrac{11}{15}:\dfrac{2}{3}=\dfrac{11}{10}\)

a) \(\dfrac{4}{7}\times x=\dfrac{5}{9}\)

           \(x=\dfrac{5}{9}\div\dfrac{4}{7}\)

          \(x=\dfrac{5}{9}\times\dfrac{7}{4}\)

          \(x=\dfrac{35}{35}\)

b) \(\dfrac{11}{15}\div x=\dfrac{2}{3}\)

     \(x=\dfrac{11}{15}\div\dfrac{2}{3}\)

     \(x=\dfrac{11}{15}\times\dfrac{3}{2}\)

     \(x=\dfrac{33}{30}\)

     \(x=\dfrac{11}{10}\)

\(x-\dfrac{2}{3}.\left(x+9\right)=1\)

\(\Rightarrow x-\dfrac{2}{3}x-6=1\)

\(\Rightarrow\dfrac{1}{3}x=7\)

\(\Rightarrow x=21\)

\(x-\dfrac{2}{3}\times\left(x+9\right)=1\)

\(x-\dfrac{2}{3}x-6=1\)

\(\dfrac{1}{3}x-6=1\)

\(\dfrac{1}{3}x=1+6\)

\(\dfrac{1}{3}x=7\)

\(x=7:\dfrac{1}{3}\)

\(x=21\)