1) 3x = 45 + 15 = 60

x = 60 : 3 = 20

2) 5x = 50 - 35 = 15

x = 15 : 5 = 3

3) (2x - 5) + 17 = 6

2x - 5 = 6 - 17

2x - 5 = -11

2x = -11 + 5

2x = -6

x = -6 : 2 = -3

4) 10 - 2(4 -3x) = -4

2(4 - 3x) = -4 - 10 = -14

4 - 3x = -14 : 2 = -7

3x = -7 - 4 = -18

x = -18 : 3 = -6

\(\left\{{}\begin{matrix}\left\{{}\begin{matrix}3x-15=45\Leftrightarrow3x=60\Leftrightarrow x=20\\35-5x=50\Leftrightarrow5x=-15\Leftrightarrow x=-3\end{matrix}\right.\\\left\{{}\begin{matrix}\left(2x-5\right)+17=6\Leftrightarrow2x+5=-11\Leftrightarrow2x=-16\Leftrightarrow x=-8\\10-2\left(4-3x\right)=-4\Leftrightarrow8-6x=14\Leftrightarrow6x=-6\Leftrightarrow x=-1\end{matrix}\right.\\\left\{{}\begin{matrix}-12+3\left(-x+7\right)=-18\Leftrightarrow-3x+21=-6\Leftrightarrow-3x=-27\Leftrightarrow x=9\\24:\left(3x-2\right)=-3\Leftrightarrow3x-2=-8\Leftrightarrow3x=-6\Leftrightarrow x=-2\end{matrix}\right.\\-45:5\left(-3-2x\right)=3\Leftrightarrow-15-10x=-15\Leftrightarrow10x=0\Leftrightarrow x=0\end{matrix}\right.\)

5) - 12 + 3(-x + 7) = -18

              3(-x+7) = -18- -12

              3(-x+7) = -30

                 -x+7 = -30 : 3

                  -x+7 = -10

                   -x    = -10 -7 = -17 

     Vậy x= 17

                   
6) 24 : (3x – 2) = -3

          ( 3x - 2)  = 24: -3 

          3x - 2 = -8 

           3x      = -8 +2

           3x      = -6 

              x     = -6:3 = -2 

Vậy x= -2
7) -45 : 5.(-3 – 2x) = 3  

             5(-3-2x) = -45: 3

              5( -3-2x) = -15 

                -3-2x      = -15 :5 

                  -3- 2x    = -3

                       2x     = -3--3

                         2x= 0

Vậy  x= 0

a.

\(10-2\left(4-3x\right)=-4\)

\(\Leftrightarrow2\left(4-3x\right)=10+4\)

\(\Leftrightarrow2\left(4-3x\right)=14\)

\(\Leftrightarrow4-3x=7\)

\(\Leftrightarrow3x=-3\)

\(\Leftrightarrow x=-1\)

b.

\(-12+3\left(-x+7\right)=-18\)

\(\Leftrightarrow3\left(-x+7\right)=-18+12=-6\)

\(\Leftrightarrow-x+7=-6:3=-2\)

\(\Leftrightarrow x=9\)

c.

\(-45:5.\left(-3-2x\right)=3\)

\(\Leftrightarrow-9.\left(-3-2x\right)=3\)

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

\(\Leftrightarrow2x=-\dfrac{8}{3}\)

\(\Leftrightarrow x=-\dfrac{4}{3}\notin Z\left(loại\right)\)

Câu này em ghi sai đề?

d.

\(3x-28=x+36\)

\(\Leftrightarrow2x=28+36\)

\(\Leftrightarrow2x=64\)

\(\Leftrightarrow x=32\)

e.

\(\left(-12\right)^2.x=56+10.13x\)

\(\Leftrightarrow144x=56+130x\)

\(\Leftrightarrow144x-130x=56\)

\(\Leftrightarrow14x=56\)

\(\Leftrightarrow x=4\)

a, (2x - 5) + 17 = 6

=> 2x - 5 + 17 = 6

=> 2x = 6 - 17 + 5

=> 2x = -6

=> x = -3

vậy_

a, (2x - 5) + 17 = 6

2x - 5 = 6 - 17

2x - 5 = -11

2x = -11 + 5

2x = -6

x = -6 : 2 = -3

b) -12 + 3.(-x + 7) = -18

3.(-x + 7) = -18 + 12

3.(-x + 7) = -6

-x + 7 = -6:3

-x + 7 = -2

-x = -2 - 7

-x = -9

x = 9

\(\left(2x-5\right)+17=6\)

\(2x-5=-11\)

\(2x=-6\)

\(x=-3\)

\(\text{1/ (2x - 5) +17 =6}\\ 2x-5=6-17\\ 2x-5=-11\\ 2x=-11+5\\ x=-6:2\\ x=-3\)

\(2x-5=-11\Leftrightarrow x=-3\)

\(\text{2/ 10 - 2(4 - 3x) = - 4}\\ 2\left(4-3x\right)=10-\left(-4\right)\\ 2\left(4-3x\right)=14\\ 4-3x=14:2\\ 4-3x=7\\ 3x=4-7\\ x=-3:3\\ x=-1\)

\(1,2x+3x-4x=\left(-2\right)^3\)

<=>\(x=-8\)

\(2,x-2x=4^2+4^0\)

<=>\(-x=16+1\)

<=>\(-x=17\)

<=>\(x=-17\)

\(3,2^3x-3^2x=|12-21|\)

<=>\(-x=9\)

<=>\(x=-9\)

\(4,x-45=2x+54\)

<=>\(x-2x=54+45\)

<=>\(-x=99\)

<=>\(x=-99\)

\(5,5x-12+23=6^7:6^5\)

<=>\(5x+11=6^2\)

<=>\(5x+11=36\)

<=>\(5x=25\)

<=>\(x=5\)