phá ngoặc lun nà:

2x-(234-(-456-543-3x))=23

2x-(234+456+543+3x)=23

2x-234-456-543-3x=23

-x-1233=23

-x=23+1233=1256

x=1256

a/\(-\left(-432-3x\right)+\left(-432-4x+21\right)=-2345\)

\(\Leftrightarrow+432+3x-432-4x+21=-2345\)\(\Leftrightarrow\left[432+\left(-432\right)\right]+\left[\left(-4x\right)+3x\right]+21=-2345\)

\(\Leftrightarrow0+-1x+21=-2345\)\(\Leftrightarrow-1x=-2345-21=-2366\)

\(\Rightarrow x=\left(-2366\right):\left(-1\right)=2366\)

b/\(12x-\left(-3546-3x\right)=\left(2x-234\right)-\left(-678-2x\right)\)

\(\Leftrightarrow12x+3546+3x=2x-234+678+2x\)

\(\Leftrightarrow15x+3546=\left(2x+2x\right)+\left[\left(-234\right)+678\right]\)

\(\Leftrightarrow15x+3546=4x+444\)

\(\Leftrightarrow15x+3546-4x-444=0\)

\(\Leftrightarrow\left(15x-4x\right)+\left(3546-444\right)=0\)

\(\Leftrightarrow11x+3102=0\)

\(\Leftrightarrow11x=0-3102=-3102\)

\(\Rightarrow x=\left(-3102\right):11=-282\)

321 + 456 - 234 = 543

543 - 123 + 456 = 876

234 + 234 - 321 = 147

a) a)321+456-234= 543

b)543-123+456=876

c)321+234-321=234

a)543

b)876

c)147

(864 x11 -432 x4 ) :[ 432 x (135-132) ]

=(9504-1728) : ( 432 x 3 )

=7776 : 1296

= 6

( click đúng nha bạn )

`a)25xx532xx4`

`=(25xx4)xx432`

`=432xx100=43200`

`b)456xx200-456xx100`

`=456xx(200-100)`

`=456xx100=45600`

\(a,25\times432\times4=25\times4\times432=100\times432=4320\\ b,456\times200-456\times100=456\times\left(200-100\right)=456\times100=45600\)

`25 xx 432 xx 4 = (25xx4 ) xx 432 = 100 xx 432 = 43200`

`456 xx200 - 456 xx 100 = 456 xx ( 200 - 100 ) = 456 xx 100 = 45600`