\(a,x-36:18=12-15\\ \Rightarrow x-2=-3\\ \Rightarrow x=-1\\ b,92-\left(17+x\right)=72\\ \Rightarrow17+x=20\\ \Rightarrow x=3\\ c,720:\left[41-\left(2x+5\right)\right]=40\\ \Rightarrow41-\left(2x+5\right)=18\\ \Rightarrow2x+5=23\\ \Rightarrow2x=18\\ \Rightarrow x=9\\ d,\left(x+2\right)^3-23=41\\ \Rightarrow\left(x+2\right)^3=64\\ \Rightarrow\left(x+2\right)^3=4^3\\ \Rightarrow x+2=4\\ \Rightarrow x=2\)

b: =>x+17=20

hay x=3

d: =>x+2=4

hay x=2

A = 1
B = 3
C = 9
D = 2

720:[41-(2x - 5)]=2³.5

 720:[41-(2x - 5)]=8.5

 720:[41-(2x - 5)]=40

        41-(2x - 5)=720:40

        41-(2x - 5)=18

       2x - 5=41-18

       2x - 5=23

        2.x=23+5

        2.x=28

        x=28:2

        x=14

720 : [ 41 - ( 2x - 5 ) ] = 2³ . 5

720 : [ 41 - ( 2x - 5 ) ] = 8 . 5

720 : [ 41 - ( 2x - 5 ) ] = 40

41 - ( 2x - 5 ) = 720 : 40

41 - ( 2x - 5 ) = 18

2x - 5 = 41 - 18

2x - 5 = 23

2x = 23 + 5

2x = 28

=> x = 28 : 2

=> x = 14

720 : [ 41 - ( 2 x - 5 ) ] = 40

          41 - ( 2 x - 5 )   = 720 : 40

          41 - ( 2 x - 5 )   = 18

                   2 x - 5     = 41 - 18

                   2 x - 5     = 23

                   2 x          = 23 + 5

                   2 x          = 28

                      x          = 28 : 2

                      x          = 14

720:[41-(2x-5)]=2³x5

720:[41-(2x-5)=8x5

720:[41-(2x-5)=40

[41-(2x5)=720:40

41-(2x5)=18

(2x-5)=41-18

2x-5=23

2x=23+5

2x=28

x=28:2

x=14

\(720:\left(41-2x-5\right)=23,5\)

<=> \(41-2x-5=\frac{1440}{47}\)

<=> \(x=2,680851064\)

\(720:\left(41-2x-5\right)=23,5\)

\(\Leftrightarrow720:36-720:2x=23,5\)

\(\Leftrightarrow20-720:2x=23,5\)

\(\Leftrightarrow-720:2x=23,5-20\)

\(\Leftrightarrow-720:2x=3,5\)

\(\Leftrightarrow2x=\frac{-1440}{7}\)

\(\Leftrightarrow x=\frac{-720}{7}\)

720 : ( 41 - 2x - 5 ) = 23.5

41 - 2x - 5 = 720 : 23.5

41 - 2x - 5 = 1440/47

36 - 2x = 1440/47

2x = 36 - 1440/47

2x = 252/47

x = 252/47 : 2

x = 126/47

=> 41 - ( 2x - 5) = 720 : 160 = 6

=> 2x - 5 = 41 - 6 

=> 2x - 5 = 35

=>2x = 40 

=> x = 20

Vậy x = 20 

Ta co: 

720:[41-(2x-5)]=120

41-(2x-5)        = 720 : 120

41 - (2x-5)      = 6

 2x  - 5          = 41 -6

2x -5             = 35

2x                 = 35 +5

2x                 = 40

x                   = 40 :2

x                   =20

​Vậy x bằng 20 

720 : [ 41 - ( 2x - 5 ) ] = 120

=>    41 - ( 2x - 5 ) = 720 : 120 = 6

=>          2x - 5 = 41 - 6 = 35

=>              2x = 35 + 5 = 40

=>                 x = 40 : 2 = 20

đúng nha !!!

720 : [ 41 - ( 2x-5)] = 2^3 .5

=> 720 :[ 41- (2x-5)] = 40

=> 41 - (2x-5) = 18

=> 2x -5 = 23

=> 2x = 28

=> x=14

720 : [ 41 - (2x - 5)] = 2³ . 5

=> 720 : [ 41 - ( 2x - 5)] = 40

=> 41 - (2x - 5) = 18

=> 2x - 5 = 23

=> 2x = 28

=> x = 14

Vậy x = 14

(2x - 4)³ = 8

(2x - 4)³ = 2³

2x - 4 = 2

2x = 2 + 4

2x = 6

x = 6 : 2

x = 3

\(\frac{720}{41-\left(2x-5\right)}=2^3\times5\)

\(\frac{720}{41-2x+5}=8\times5\)

\(46-2x=\frac{720}{40}\)

\(2x=46-18\)

2x = 28

x = 28 : 2

x = 14