\(123\cdot456+456\cdot321-256\cdot444\)

\(=\left(123+321\right)\cdot456-256\cdot444\)

\(=444\cdot456-256\cdot444\)

\(=444\cdot\left(456-256\right)\)

\(=444\cdot200\)

\(=88800\)

là 88800

hok tốt

                      Bài làm :

123 x 456 + 456 x 321 - 256 x 444 = 56088 + 146376 - 113664

                                                        = 88800

                       Đ/S : 88800 

Ta có: \(123\times456+456\times321-256\times444\)

           \(=444\times456-256\times444\)

           \(=444\times\left(456-256\right)\)

            \(=444\times200\)

            \(=444\times200=88800\)

de minh giup ban. bai do lam the nay

123 x 456 + 228 x 642 - 256 x 444

=56088 + 146376 - 113664

=202464 -113664

=88800

   neu sai cac ban nho sua cho minh, neu dung thi cac ban h cho to nhe

123 x 456 + 228 x 642 - 256 x 444 = 88800 (Nhớ clik cho tớ với nhá!)

minh klich cho bạn rồi đấy

\(\left(100+58\right)\times58+\left(200-42\right)\times12\)

\(=158\times58+158\times12\)

\(=158\times\left(58+12\right)\)

\(=158\times70=11060\)

\(128\times72+14\times256\)

\(=128\times72+14\times2\times128\)

\(=128\times\left(72+28\right)\)

\(=128\times100=12800\)

\(157\times99+123+34\)

\(=157\times99+157\times1\)

\(=157\times\left(99+1\right)\)

\(=157\times100=15700\)

\(67+98\times45+23\)

\(=98\times45+90\)

\(=98\times45+45\times2\)

\(=45\times\left(98+2\right)\)

\(=45\times100=4500\)

a/  3 1 3 - 1 3 4 =   10 3 - 7 4 = 40 12 - 21 12 = 40 - 21 12 = 19 12

b/  2 5 6 + 1 2 3 =  17 6 + 5 3 = 17 6 + 10 6 = 17 + 10 6 = 27 6 = 9 2

c/  2 3 8   :   1 3 4  =   19 8 : 7 4 = 19 8 × 4 7 = 19 × 4 8 × 7 = 76 56 = 19 14

d/  1 3 7   x   1 5 8  =  10 7 × 13 8 = 10 × 13 7 × 8 = 130 56 = 65 28

\(37\times7+80\times3+34\times7\)

\(=7\times\left(37+34\right)+80\times3\)

\(=7\times71+240\)

\(=497+240\)

\(=737\)

a)

37 x 7 + 80 x 3 + 34 x 7

= 7 x (37 + 34) + 80 x 3

= 7 x 71 + 240

= 497+ 240 

= 737

b)

123 x 456 + 456 x 321 - 256 x 444

= 456 x (123 + 321) - 256 x 444

= 456 x 444 - 256 x 444

= 444 x (456 - 256)

= 444 x 200

= 88800

k mk nhé ^^

x =  [{(15129 x 123 ) : 123 } :123] : 123

x = 1

X=0 nha bạn

256x57+256xX=25600

x=25600/256

x=100

x=100-57

x=43

x=......................

x + 123 = 123 - 123 + 123

x + 123 = 123

x = 123 - 123

x = 0

x + 123 = 123 - 123 + 123

x + 123 =0 + 123

x + 123 =123 

x = 123 - 123 

x = 0

K MIK NHÉ!

x + 123 = 123 - 123 + 123

x = 123 - 123 + 123 - 123

x = 0