7 x 8 = 56       16 : 2 = 8       36 : 6 = 6       49 : 7 = 7

2 x 5 = 10       72 : 8 = 9       9 x 3 = 27       63 : 7 = 9

6 x 4 = 24       25 : 5 = 5       4 x 8 = 32       7 x 5 = 35

7 x 8 = 56

2 x 5 = 10

6 x 4 = 24

16 : 2 = 8 

72 : 8 = 9

25 : 5 = 5

36 : 6 = 6

9 x 3 = 27

4 x 8 = 32

49 : 7 = 7

63 : 7 = 9

7 x 5 = 35

a/   100 . 37 + 37. 37 + 200 . 63 - 63 . 63\

  =  37 .[ 100+ 37 ]   + 63 . [ 200 - 63 ]  

  =    37. 137             +  63 . 137 

  =    137. [ 37 + 63 ] 

  =   137 . 100 = 13700

b/  84 + 14 .6 + 7 . 12 + 21. 4 + 3.28 

=  84 + 84 +  84 + 84 +84

= 84. 5 = 420 

[ dấu " ." là " x" nha ] đừng quên tích cho tui 

a, 13700

cảm ơn anh NTN và bạn no_nickname nhé ! :))))

x = 5/6- 4/7

x= 11/42

x = 7/12: 3/4

x = 7/9

x = 5/6- 4/7

x= 11/42

x = 7/12: 3/4

x = 7/9

a)\(\dfrac{x}{60}=-\dfrac{3}{4}\)

\(\Rightarrow x\cdot4=60\cdot\left(-3\right)\)

   \(x\cdot4=-180\)

  x=45

b)\(\dfrac{2}{5}=\dfrac{12}{x}\)

   \(\Rightarrow2x=5\cdot12\)

      \(2x=60\)

       x=30

c)\(x-\dfrac{5}{7}=\dfrac{6}{21}\)

      \(x=\dfrac{2}{7}+\dfrac{5}{7}\)

      x=1

d)\(x+\dfrac{7}{8}=\dfrac{63}{24}\)

     \(x=\dfrac{21}{8}-\dfrac{7}{8}\)

     \(\dfrac{14}{8}\)

a)\(\dfrac{x}{60}=\dfrac{-3}{4}\Rightarrow x=\dfrac{-3.60}{4}=-45\)

b)\(\dfrac{2}{5}=\dfrac{12}{x}\Rightarrow x=\dfrac{5.12}{2}=30\)

ai help vs  :(((

275-(113+x)+63=158
275-(113+x)=95
113+x=175-95
113+x=80
x=80-113
x=33

[3(x+2):7]4=120
3(x+2):7=30
3(x+2)=210
x+2=70
x=68

2: =>(3x-7)^2=25/144=(5/12)^2

=>3x-7=5/12 hoặc 3x-7=-5/12

=>3x=5/12+7=89/12 hoặc 3x=7-5/12=79/12

=>x=89/36 hoặc x=79/36

3:Sửa đề: |2x-3|=|x+1|

=>2x-3=x+1 hoặc 2x-3=-x-1

=>x=4 hoặc 3x=2

=>x=2/3 hoặc x=4

4: =>3x+1=5 hoặc 3x+1=-5

=>3x=4 hoặc 3x=-6

=>x=-2 hoặc x=4/3

1: =>\(2x-7=\sqrt[3]{\dfrac{26}{63}}\)

=>\(2x=\sqrt[3]{\dfrac{26}{63}}+7\)

=>\(x=\dfrac{1}{2}\cdot\left(\sqrt[3]{\dfrac{26}{63}}+7\right)\)

14x6=

c: Ta có: \(\dfrac{2}{5}\cdot\left[\left(\dfrac{3}{5}\right)^2:\left(-\dfrac{1}{5}\right)^2-7\right]\cdot\left(1000\right)^0\cdot\left|-\dfrac{11}{15}\right|\)

\(=\dfrac{2}{5}\cdot\left(\dfrac{9}{25}:\dfrac{1}{25}-7\right)\cdot1\cdot\dfrac{11}{15}\)

\(=\dfrac{2}{5}\cdot\dfrac{11}{15}\cdot2\)

\(=\dfrac{44}{75}\)

a) X : 4 = 58                                                     b) 7 x X = 63

         X = 58 x 4                                                         X = 63 : 7

          X = 232                                                            X = 9

9 x 5 = 45

63 : 7 = 9

8 x 8 = 64

5 x 7 = 35

8 x 7 =56

3 x 8 = 24

40 : 5 = 8

5 x 5 = 25

7 x 5 = 35

7 x 8 =56

6 x 4 = 24

45 : 9 = 5

7 x 7 = 49

35 : 5 = 7

56 : 8 = 7

2 x 8 = 16

81 : 9 = 9

9 x 9 = 81

35 : 7 = 5

56 : 7 = 8

ay bạn ơi dễ vậy mà