=> X x 18= 18000+594

=> X x 18=18594

=> X=18594:18

=> X=1033

x *18 - 594 = 18000
x * 18 = 18000 + 594
x * 18 = 18594
x = 18594 : 18
x = 1033

X x 18 - 594 = 18 000

X x 18         = 18 594

X                = 18 594 : 18 

X                =    1033

264+12x=1800

12x=1536

x=128

(x+73):19=321

x+73=6099

x=6026

2x+3x+4x=18

9x=18

x=2

10<2x<20

=>5<x<10

x=6,7,8,9

\(264+12x=1800\)

\(\Leftrightarrow12x=1536\)

\(\Leftrightarrow x=128\)

==============

\(\left(x+73\right):19=321\)

\(\Leftrightarrow x+73=6099\)

\(\Leftrightarrow x=6026\)

===============

\(2x+3x+4x=18\)

\(\Leftrightarrow x.\left(2+3+4\right)=18\)

\(\Leftrightarrow x.9=18\)

\(\Leftrightarrow x=2\)

================

\(10< 2x< 20\)

..................................

\(2x=12\Leftrightarrow x=6\)

\(2x=14\Leftrightarrow x=7\)

\(2x=16\Leftrightarrow x=8\)

\(2x=18\Leftrightarrow x=9\)

\(x\in\left\{6;7;8;9\right\}\)

bn hỏi 1 lần thôi đừng đăng nhiều chật lắm

12x = 1800 - 264

12x = 1536

x = 1536 : 12

x = 128

( x + 73 ) : 19 = 321

( x + 73 ) = 321 x 19

 x + 73 = 6099

x = 6099 - 73

x = 6026

2x + 3x + 4x = 18 

x . ( 2 + 3 + 4 ) = 18

x .          9          = 18

x = 18 : 9

x = 2

10 < 2x < 20

x = 6 ; 7 ; 8 ; 9

Đáp án A

bai nay ap dung tinh chat day ti so = nhau

Ta có:9xX=1800

X=1800:9

X=200

9 x X = 1800

x = 1800  : 9 

x = 200

x:[(1800+600):30]=560:(315-15)

=> x:[2400:30]=560:300

=> x: 80 = 560:300

=> x = (80 x 560): 300

=> x = 448/3 =  149,(3)

\(\dfrac{x}{6}=\dfrac{y}{12}=k\) \(\Rightarrow\left\{{}\begin{matrix}x=6k\\y=12k\end{matrix}\right.\)

\(\Rightarrow xy=72k^2=1800\Rightarrow k=\pm5\)

\(\Rightarrow\left[{}\begin{matrix}\left\{{}\begin{matrix}x=30\\y=60\end{matrix}\right.\\\left\{{}\begin{matrix}x=-30\\y=-60\end{matrix}\right.\end{matrix}\right.\)

x : [(1800 + 600) : 30] = 560 : (315 - 35)

x : (2400 : 30) = 560 : 280

x : 80 = 2

x = 2 x 8 0

x = 160 

Bằng 160,.đúng rồi!!!

x:(2400: 30) = 560 : 280

x: 80 = 2

x       = 2.80

x       = 160

Vậy x = 160