212 552 : x = 326
                x = 212552 : 326
                x = 652

\(212552:x=326\\ x=212552:326\\ x=652\)

652

phân tích ra cái j vậy

x : 637 = 2345

=>x= 2345 x 637

=> x =1493765

4000 - x =138

=> x =4000 - 138

=> x = 3862

212552 : x = 326

=>x = 212552 : 326

=> x =652

( x + 1233 ) - 1978 = 9876

=>(x+1233) = 11854

=> x =10621

x : 2 : 3 = 138

=>x:2 = 138 . 3 = 414

=> x = 828

x : 637 = 2345

<=> x = 2345 . 637

<=> x = 1493765

#hoc_tot#

1. 234 + ( 345 - x ) = 500

345 - x = 500 - 234

345 - x = 266

x = 345 - 266

x = 79

2. 456 - ( x + 23 ) = 326

x + 23 = 456 - 326

x + 23 = 130

x = 130 - 23

x = 107

3. ( 567 - x ) . 212 = 605

567 - x = 605 : 212

567 - x = ...

=> Đề sai

4. ( 5 . x - 15 ) : 5 = 0

5 . x - 15 = 0 : 5

5 . x - 15 = 0

5 . x = 0 + 15

5 . x = 15

x = 15 : 5

x = 3

5. 14 x ( x - 7 ) = 210

x - 7 = 210 : 14

x - 7 = 15

x = 15 + 7

x = 22

6. 84 - 4 x ( 2 . x + 1 ) = 48

4 x ( 2 . x + 1 ) = 84 - 48

4 x ( 2 . x + 1 ) = 36

2 . x + 1 = 36 : 4

2 . x + 1 = 9

2 . x = 9 - 1

2 . x = 8

x = 8 : 2

x = 4

1. 345 - x = 500 - 234

345-x=266

x=345-266

x=79

2. x+23 =456-326

x+23=130

x=130-23

x=107

4. 5 x X - 15 =5 x0 

5xX -15=0

5 x X = 0+15

5x X = 15

X = 15:5

X =3

5 . x-7 = 210 :14

x - 7 =15

x=15+7

x=22

326

326 + 326x8 + 326

= 326x(1+8+1)

= 326x10

= 3260

\(\frac{x+2}{327}+\frac{x+3}{326}+\frac{x+4}{325}+\frac{x+5}{324}+\frac{x+349}{5}=0\)

\(\Leftrightarrow\frac{x+2}{327+1}+\frac{x+3}{326+1}+\frac{x+4}{325+1}+\frac{x+5}{324+1}+\frac{x+349}{5-4}=0\)

\(\Leftrightarrow\frac{x+329}{327}+\frac{x+329}{326}+\frac{x+329}{325}+\frac{x+329}{324}+\frac{x+329}{5}=0\)

\(\Leftrightarrow\left(x+329\right)\cdot\left(\frac{1}{327}+\frac{1}{326}+\frac{1}{325}+\frac{1}{324}+\frac{1}{5}\right)=0\)

Do \(\left(\frac{1}{327}+\frac{1}{326}+\frac{1}{325}+\frac{1}{324}+\frac{1}{5}\right)\ne0\)

Nên \(x+329=0\Rightarrow x=-329\)

a) \(\left(x+1\right)\left(x+2\right)=272\)

\(\Rightarrow x^2+3x+2=272\)

\(\Rightarrow x^2+3x-270=0\)

\(\Rightarrow x^2+18x-15x-270=0\)

\(\Rightarrow x\left(x+18\right)-15\left(x+18\right)=0\)

\(\Rightarrow\left(x+18\right)\left(x-15\right)=0\)

\(\Rightarrow\left[{}\begin{matrix}x+18=0\\x-15=0\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}x=-18\\x=15\end{matrix}\right.\)

d) \(\left(x+4\right)\left(x+5\right)=552\)

\(\Rightarrow x^2+9x+20=552\)

\(\Rightarrow x^2+9x-532=0\)

\(\Rightarrow x^2+28x-19x-532=0\)

\(\Rightarrow x\left(x+28\right)-19\left(x+28\right)=0\)

\(\Rightarrow\left(x+28\right)\left(x-19\right)=0\)

\(\Rightarrow\left[{}\begin{matrix}x+28=0\\x-19=0\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}x=-28\\x=19\end{matrix}\right.\)

2 bạn sai rồi!!!

Bài 1:

  (a x 1 - a : 1) x 26 x a

=(a - a) x 26 x a

= 0 x 26 x a

0

Bài 2:

  326 + 326 x 8 + 326

=326 x1 + 326 x 8 + 326 x 1

=326 x (1 + 8 + 1)

=326 x 10

=3260

Bài 3:

888 + 88 + 8 + 8 + 8 = 1000