\(720:\left[41-\left(2x-5\right)\right]=40\)                                      \(3x+8x-30=25\)

\(41-\left(2x-5\right)=18\)                                                     \(3x+8x=55\)

\(2x-5=23\)                                                                    \(11x=55\)

\(2x=28\)                                                                                  \(x=5\)

\(x=14\)

720:[41-(2.X-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-(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

\(720:\left[41-\left(2.x:5\right)\right]=120\)

\(\left[41-\left(2.x:5\right)\right]=720:120\)

\(41-\left(2.x:5\right)=6\)

\(2.x:5=41-6\)

\(2.x:5=35\)

\(2.x=35.5\)

\(2.x=175\)

\(x=\dfrac{175}{2}\)

Câu 1: 

                         [(4x+28).3+5.5]:5=35

                         [(4x+28).3+5.5]=35.5 

                         (4x+28).3+25=175 

                          (4x+28).3=175-25

                          (4x+28).3=150 

                         4x+28=150:3 

                          4x+28=50 

                           4x=50-28 

                             4x=22 

                            x=22:4 

                            x=5,5

a.\([\)(4x+28).3+5.5\(]\):5=35\(\Leftrightarrow\)4(x+7).3+25=175\(\Leftrightarrow\)4(x+7).3=150\(\Leftrightarrow\)4.(x+7)=50\(\Leftrightarrow\)x+7=\(\frac{25}{2}\)\(\Leftrightarrow\)x=\(\frac{11}{2}\)

b.720:\([\)41-(2x-5)\(]\)=40\(\Leftrightarrow\)41-(2x-5)=18\(\Leftrightarrow\)2x-5=23\(\Leftrightarrow\)x=14

c.3x+8x-30=25\(\Leftrightarrow\)11x=55\(\Leftrightarrow\)x=5

a) [( 4x + 28 ) . 3 + 5.5 ] : 5 = 35

\(\Leftrightarrow\)[( 4x + 28 ) . 3 + 25 ] = 35.5 = 175

\(\Rightarrow\left(4x+28\right).3=175-25=150\)

\(\Rightarrow4x+28=150:3=50\)

\(\Rightarrow4x=50-28=22\)

\(\Rightarrow x=\frac{22}{4}=\frac{11}{2}=5,5\)

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

\(\Rightarrow41-\left(2x-5\right)=720:40=18\)

\(\Rightarrow2x-5=41-18=23\)

\(\Rightarrow2x=23+5=28\)

\(\Rightarrow x=28:2=14\)

c) 3 . x + 8 . x - 30 = 25

\(\Rightarrow x\left(3+8\right)-30=25\)

\(\Rightarrow11x=25+30=55\)

\(\Rightarrow x=55:11=5\)

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

   41 - ( 2x - 5 ) = 720 : 40 

   41 - ( 2x - 5 ) = 18

    2x - 5 = 41 - 18

    2x - 5 = 23

2x = 28

x = 14

k nha , minh k lai

720/[41-(2x-5)]=40 
<=>41-(2x-5)=18 
2x-5=23 
x=14. 
3636/(12x-91)=36 
12x-91=101 
12x=192 
x=16.

Nguồn:xmen

aihihi

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k mk nhé

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

\(\Leftrightarrow\left[41-\left(2x-5\right)\right]=720:40\)

\(\Leftrightarrow41-\left(2x-5\right)=18\)

\(\Leftrightarrow2x-5=41-18\)

\(\Leftrightarrow2x-5=23\)

\(\Leftrightarrow2x=28\)

\(\Leftrightarrow x=14\)

a: \(\left[\left(10-x\right)\cdot2+51\right]:3-2=3\)

=>\(\left[2\left(10-x\right)+51\right]:3=5\)

=>\(\left[2\left(10-x\right)+51\right]=15\)

=>\(2\left(10-x\right)=15-51=-36\)

=>10-x=-36/2=-18

=>\(x=10-\left(-18\right)=10+18=28\)

b: \(\left(x-12\right)-15=20-\left(17+x\right)\)

=>\(x-12-15=20-17-x\)

=>\(x-27=3-x\)

=>\(2x=30\)

=>\(x=\dfrac{30}{2}=15\)

c: \(720-\left[41-\left(2x-5\right)\right]=2^3\cdot5\)

=>\(720-\left[41-2x+5\right]=8\cdot5=40\)

=>\(\left[41-2x+5\right]=720-40=680\)

=>-2x+46=680

=>-2x=680-46=634

=>\(x=\dfrac{634}{-2}=-317\)

Ta có :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 = 25

=> 2x      = 25 + 5

=> 2x      = 30

=>  x       = 30 : 2

=>  x       = 15

Vậy x = 15

720:[41-(2x-5)]=8.5

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

2x-5=41-18

2x-5=23

2x=28

x=14

Vậy x=14

Mk viết 2.x là 2x nha bạn, k cho mk nha

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

=>41-(2x-5)=13

=>2x-5=41-13

=>2x-5=28

=>x=(28+5):2

=>x=33/2