`a, 504 : (16-3x)=72`

`<=> 16-3x=7`

`<=>3x=9`

`<=>x=3`

`b,272-(4x+15)=45`

`<=>4x+15=227`

`<=>4x=212`

`<=>x=53`

a: =>16-3x=504:72=7

=>3x=9

=>x=3

b: =>4x+15=272-45=227

=>4x=212

=>x=53

a) 504 : (16 - 3\(\times\)x) = 72

=> 16 - 3\(\times\)x = 7

=> 3\(\times\)x = 9

=> x = 3

d) 272 - (4\(\times\)x + 15) = 45

=> 4\(\times\)x + 15 = 227

=> 4\(\times\)x = 212

=> x = 53

\(\Rightarrow16-3x=504:72=7\\ \Rightarrow3x=16-7=9\Rightarrow x=3\\ \left(2^2\cdot x-5^2\right)\cdot3^8=3^9\\ \Rightarrow4x-25=3^9:3^8=3\\ \Rightarrow4x=28\Rightarrow x=7\)

504 : (16 - 3x) = 72 (ĐK: \(x\ne\dfrac{16}{3}\))

<=> 16 - 3x = 504 : 72

<=> 16 - 3x = 7

<=> 16 - 7 = 3x

<=> 3x = 9

<=> x = 3 (tM)

(2²x - 5²) . 3⁸ = 3⁹

<=> (4x - 25) . 6561 = 19683

<=> 4x - 25 = 19683 : 6561

<=> 4x - 25 = 3

<=> 4x = 3 + 25

<=> 4x = 28

<=> x = 7 

Tham khảo : 

\(272+\left(146-x\right)=118\)

\(146-x=118-272\)

\(146-x=-154\)

\(x=146-\left(-154\right)\)

\(\Rightarrow x=300\)

\(504:\left(16-3x\right)=72\)

\(16-3x=504:72\)

\(16-3x=7\)

\(3x=16-7\)

\(3x=9\)

\(x=9:3\)

\(\Rightarrow x=3\)

1=> 146-x=-154

=>x=300

2> =>16-3x=7

=>3x=9

=>x=3

a, 272 + ( 146 - x ) = 118

146 - x = 118 - 272

146 - x = -154

x = 146 - ( -154 )

x = 300

Vậy....

b, 504 : ( 16 - 3x ) = 72 

16 - 3x = 7

3x = 16 - 7 

3x = 9

x = 3

Vậy.....

a) x = 3

b) x = 53

c) x = 2024

d) x = 6

a,504:[16-3.x]=72

          16-3.x=504:72

          16-3.x=7

          3.x     =16-7

          3.x     =9

            \(\Rightarrow x=3\)

          b,272-[4.x+15] = 45

                   4.x+15  = 272-45

                   4.x+15  = 227

                   4.x        = 227-15

                   4.x        = 212

                      x        = 212:4

                      \(\Rightarrow x=53\)

                     c,425-x:8 =91

                              x:8 =425-91

                              x:8 =334

                              x    =334x8

                              \(\Rightarrow x=2672\)

                     d,  293-8.27+x.25=80

                         293-216 +x.25=80

                         77+x.25         =80

                               x.25         =3

                               \(\Rightarrow x=\frac{3}{25}\)

x = 3

x = 53

x = 2672

x = 3 / 25

ai thấy đúng thì ủng hộ mk nha

504:[16-3x]=72

16-3x=504:72

16-3x=7

3x=16-7

3x=9

x=9:3

x=3

Vậy x=3

272-(4x+15)=45

4x+15=272-45

4x+15=227

4x=227-15

4x=212

x=212:4

x=53

Vậy x=53

425-x:8=91

x:8=425-91

x:8=334

x=334.8

x=2672

Vậy x=2672

293-8.27+x.25=80

77+x.25=80

x.25=80-77

x.25=3

x=3:25

x=\(\frac{3}{25}\)

Vậy x=\(\frac{3}{25}\)

\(a,\Leftrightarrow x+9=39\Leftrightarrow x=30\\ b,\Leftrightarrow73-x=69\Leftrightarrow x=4\\ c,\Leftrightarrow x+7=38\Leftrightarrow x=31\\ d,\Leftrightarrow x+4=178\Leftrightarrow x=174\\ e,\Leftrightarrow2\left(x-51\right)=16+20=36\Leftrightarrow x-51=18\Leftrightarrow x=69\\ f,\Leftrightarrow x-19=9\Leftrightarrow x=28\\ g,\Leftrightarrow4\left(x-3\right)=49-1=48\Leftrightarrow x-3=12\Leftrightarrow x=15\)

a) 45 - ( x + 9 ) = 6

45 - x = 6 + 9

45 - x = 15

x = 45 - 15

x = 30

b) 89 - ( 73 - x ) = 20

89 - x = 20 + 73

89 - x = 93

x = 93 - 89

x = 4

c) 198 - ( x + 4 ) = 120

198 - x = 120 + 4

198 - x = 124

x = 198 - 124

x = 74

d) ( x + 7 ) - 25 = 13

x - 25 = 13 + 7

x - 25 = 20

x = 20 + 25

x = 45

e) 2 ( x - 51 ) = 2.2³ + 20

2 ( x - 51 ) = 64 + 20

2 ( x - 51 ) = 84

x - 51 = 84 - 2

x - 51 = 82

x = 82 + 51

x = 133

f) 450 : ( x - 19 ) = 50

450 : x = 50 - 19

450 : x = 41

x = 450 : 41

x = 24

504 : ( 16 - 3x ) = 72

           16 - 3x  = 504 : 72

            16 - 3x = 7

                   3x = 16 - 7

                   3x = 9

                    x = 9 : 3

                    x = 3