a) 456 + ( x - 357 ) = 1362

x - 357=1362-456

x - 357=906

x=906+357

x=1263

b) ( 2345 - x) - 183 = 2014

 2345 - x=2014+183

 2345 - x=2197

x=2345-2197

x=148

c) ( x - 2005 ) . 2006 = 0

x - 2005 =0:2006

x - 2005 =0

x=0+2005

x=2005

d) 480 + 45 . 4 = ( x + 125) : 5 + 260

480 + 180 = ( x + 125) : 5 + 260

660=( x + 125) : 5 + 260

( x + 125) : 5 + 260=660

( x + 125) : 5=660-260

( x + 125) : 5=400

 x + 125 =400.5

 x + 125 =2000

x=20000-125

x=1975

e) 2005 . ( x - 2006) =2005

x - 2006=2005:2005

x - 2006=1

x=1+2006

x=2007

g) [( x + 50) . 50 - 50] : 50 = 50

( x + 50) . 50 - 50=50.50

( x + 50) . 50 - 50=2500

( x + 50) . 50=2500+50

( x + 50) . 50=2550

x + 50=2550:50

x + 50=51

x=51-50

x=1

Bạn Huyền ơi ở chỗ câu d mình ko hiểu tại sao 400.5=2000 mà ở dưới lại ghi 20000-125

nhầm

câu c : 

=> 480 + 180 = (x + 125) : 5 + 260

=> 660 = (x + 125) : 5 + 260

=> (x + 125) : 5 = 400

=> x + 125 = 2000

=> x = 1875

câu e :

=> (x + 50) . 50 - 50 = 2500

=> (x + 50) . 50 = 2550

=> x + 50 = 51

=> x = 1

a/ = (195 - 195) : (1945 + 1014) = 0 : (1945 + 1014) = 0

b/ => x - 2005 = 0 => x = 0 + 2005 = 2005

c/ => 480 + 180 = (x + 125) : 5 + 260

=> 300 = (x + 125) : 5 + 260

=> (x + 125) : 5 = 40 

=> x + 125 = 8 

=> x = -117

d/ => x - 2006 = 1 => x = 2007

e/ => (x + 50) . 50 - 50 = 1

=> (x + 50) . 50 = 51

=> x + 50 = 51/50

=> x = -2449/50

a)(x-2005).2006=0

=>x-2005=0

=>x=2005

b)480+45.4=(x+125):5+260

=>480+180=(x+125):5+260

=>660=(x+125):5+260

=>(x+125):5=400

=>x+125=2000

=>x=1875

c)2005.(x-2006)=2005

=>x-2006=1

=>x=2007

d){(x+50).50-50}:50=50

=>(x+50).50-50=2500

=>(x+50)*50=2550

=>x+50=51

=>x=1

a) (x - 2005 ) . 2006 = 0

x - 2005 = 0 : 2006

x - 2005 = 0

x = 0 + 2005

x = 2005

b) 2005.(x-2006) = 2005

x - 2006 = 2005 : 2005

x - 2006 = 1

x = 1 + 2006

x = 2007

c) 480+45.4=(x+125) : 5 + 260

480 + 180 = (x+125) : 5 + 260

660 = ( x + 125 ) : 5 + 260

660 - 260 = ( x+ 125 ) : 5

400 = ( x + 125 ) : 5

400 x 5 = x + 125

2000 = x + 125

2000 - 125 = x

1875 = x

tương tự

231321131

1231231

4564646+

3123165

1564156

(x - 2005) x 2006 = 0

<=> x - 2005 = 0 

<=> x = 2005

Vậy x = 2005

\(456+\left(x-357\right)=1362\)                        \(\left(2345-x\right)-183=2014\)        

\(x-357=906\)                                               \(2345-x=2197\)

\(x=1263\)                                                            \(x=148\) 

\(\left(x-2005\right).2006=0\)          Phần sau tương tự thế !

\(x-2005=0\)

\(x=2005\)

\(a,456+\left(x-357\right)=1362\)

\(x-357=1362-456\)

\(x-357=906\)

\(x=1263\)

\(b,\left(2345-x\right)-183=2014\)

\(2345-x=2197\)

\(x=148\)

\(c,\left(x-2005\right)\times2006=0\)

\(x-2005=0\)

\(x=2005\)

\(d,480+45\times4=\left(x+125\right):5+260\)

\(480+180=\left(x+125\right):5+260\)

\(660=\left(x+125\right):5+260\)

\(400=\left(x+125\right):5\)

\(x+125=2000\)

\(x=1875\)

\(e,2005\times\left(x-2006\right)=2005\)

\(x-2006=1\)

\(x=2007\)

\(g,[\left(x+50\right)\times50-50]:50=50\)

\(\left(x+50\right)\times50-50=2500\)

\(\left(x+50\right)\times50=2550\)

\(x+50=51\)

\(x=1\)

-4023632.5964

Số x xuất hiện trong phép tính:1+(50-2)/2+1=26(lần).Ta có:

(Xx26)+(2+4+6+...+50)=676

(Xx26)+[(50+2)x26:2]=676

(Xx26)+676=676

Xx26=0

X=0:26

X=0

Vậy X=0

X = 0 nhé

mình giúp đc câu b thôi nha

b. x + (x+2) + (x+4) +...+ (x+50)=676 (26 số hạng)

= (x + x + x + x +.....+x) + (2 + 4 + 6 + ..... + 50) = 676 (26 x ; 25 số hạng)

= 26x + ( (50 + 2) * 25 : 2) = 676

= 26x + 650 = 676

26x = 676 - 650

26x = 26

x = 26 : 26

=> x = 1

Bạn tham khảo nhé!!!!!

a)x-2006=1=>x=2006

b)(x+50)*50-50=2500

(x+50)*50=2550

x+50=51

x=1

Tick Nha