=> ( x - 12 - 15 ) - ( 20 - 7 - 18 - x ) = 0

x - 12 - 15 - 20 + 7 + 18 + x = 0

x - 12 - 15 - 20 + 7 + 18 + x = 0

2x - 12 - 15 - 20 + 7 + 18 = 0 

2x = 0 - 18 - 7 +20 + 15 + 12 

2x = 22

x = 22 : 2

x = 11

\(\left(x-12\right)-15=\left(20-7\right)-\left(18+x\right)\)

\(x-12-15=20-7-\left(18+x\right)\)

\(x-12-15=x-27\)

\(20-7-\left(18+x\right)=-\left(x+5\right)\)

\(x-27=-\left(x+5\right)\)

\(x-27=-x-5\)

\(2x=22\)

\(x=11\)

(x-12)-15=(20-27)-(18+x)

x-12-15=(-7)-18-x

x-(12+15)=(-7)+(-18)-x

x-27=-25-x

x+x=-25-(-27)

2x=-25+27

2x=2

x=2:2

x=1

Vậy x=1

\(\left(x-12\right)-15=\left(20-7\right)-\left(18+x\right)\)

\(\Leftrightarrow x-12-15=13-18-x\)

\(\Leftrightarrow x-27=-5-x\)\(\Leftrightarrow x+x=-5+27\)

\(\Leftrightarrow2x=22\)\(\Leftrightarrow x=11\)

Vậy \(x=11\)

x - 12 - 15 = 13 - 18 - x

x + x          = 13 - 18 + 12 + 15

2x              = 22

   x             = 22 : 2

   x             = 11

Bài này cần nắm quy tắc chuyển vế đổi dấu và phá ngoặc đổi dấu thôi em ^^

<=> x - 12 - 15 = 13 - 18 - x

<=> x + x          = 13 - 18 + 12 + 15

<=>   2x            = 22

<=>   x              = 22 : 2

<=>   x              = 11

TK@@@@@@@@@@@@@@@@@@

<=> x - 12 - 15 = 13 - 18 - x

<=> x + x          = 13 - 18 + 12 + 15

<=>   2x            = 22

<=>   x              = 22 : 2

<=>   x              = 11

\(\Rightarrow x-12-15=20-7-18-x\)

\(\Rightarrow x-27=-5-x\)

\(\Rightarrow x+x=27-5\)

\(\Rightarrow2x=22\)

\(\Rightarrow x=11\)

vậy x=11

lay ong di qua lay ba di lai cho xin may tick
 

\(\left(x-12\right)-15=\left(20-7\right)-\left(18+x\right)\)

\(\Rightarrow x-12-15=13-18-x\)

\(\Rightarrow x-27=-5-x\)

\(\Rightarrow x+x=27-5\)

\(\Rightarrow2x=22\)

\(\Rightarrow x=\frac{22}{2}\)

\(\Rightarrow x=11\)

x-12-15=20-7-18-x

x-27     = -5-x

suy ra x-27+5+x=0

          2x-25=0

             x=0+25=25

k mình nha

x - 12 - 15 = 13 - 18 - x

x - 27 = -5 - x

x + x = -5 + 27

2x = 22

=> x = 22 : 2 = 11

a) ( x - 12 ) - 15 = ( 20 - 7 ) - ( 18 + x )

 x - 27 = 13 - 18 - x

x + x = 13 - 18 + 27

2x = 22

x= 22 : 2 =11

Giải:
\(\left(x-12\right)-15=\left(20-7\right)-\left(18+x\right)\)
\(x-27=13-18-x\)
\(x+x=13-18+27\)
\(2x=22\)
\(x=22:2\)
\(x=11\)