(2x-6)(2x-18)=0

\(\Rightarrow\hept{\begin{cases}2x-6=0\\2x-18=0\end{cases}}\Rightarrow\hept{\begin{cases}2x=6\\2x=18\end{cases}}\Rightarrow\hept{\begin{cases}x=3\\x=9\end{cases}}\)

Vậy ...

2x-6.18

2x-108

x=108:2

x=54

Đặt \(x^2-2x+3=t\Rightarrow2x-x^2+6=9-t\)

Pt trở thành:

\(t\left(9-t\right)=18\Leftrightarrow t^2-9t+18=0\)

\(\Rightarrow\left[{}\begin{matrix}t=3\\t=6\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}x^2-2x+3=3\\x^2-2x+3=6\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x^2-2x=0\\x^2-2x-3=0\end{matrix}\right.\) (bấm máy)

\(2x\left(x+4\right)-2x^2-6=18\)

\(2x^2+8x-2x^2=18+6\)

\(8x=24\)

\(x=3\)

x + 18 = 6 - 2x

x + 2x = 6 - 18

      3x = - 12

        x = ( - 12 ) : 3

        x = - 4 

x+18=6-2x

=>18-6=2x-x

=>12=x

vậy. x=12

\(\left(2x-6\right)\left(3x-18\right)=0\)

\(\Rightarrow\orbr{\begin{cases}2x-6=0\\3x-18=0\end{cases}}\Rightarrow\orbr{\begin{cases}2x=6\\3x=18\end{cases}}\Rightarrow\orbr{\begin{cases}x=3\\x=6\end{cases}}\)

(2x - 6).(3x - 18) = 0

=> \(\orbr{\begin{cases}2x-6=0\\3x-18=0\end{cases}}\)=> \(\orbr{\begin{cases}2x=6\\3x=18\end{cases}}\)=> \(\orbr{\begin{cases}x=3\\x=6\end{cases}}\)

(2x-6).(3x-18)=0

<=> 2x-6=0 hoac 3x-18=0

<=> x=3hoac x=6

\(\left(2x-6\right).\left(3x-18\right)=0\)

\(\Rightarrow\hept{\begin{cases}2x-6=0\\3x-18=0\end{cases}\Rightarrow\hept{\begin{cases}2x=6\\3x=18\end{cases}\Rightarrow}\hept{\begin{cases}x=2\\x=6\end{cases}}}\)

a) Ta có: \(\left(2x-5\right)^3=216\)

\(\Leftrightarrow2x-5=6\)

\(\Leftrightarrow2x=11\)

hay \(x=\dfrac{11}{2}\)

b) Ta có: \(2x-3⋮x+4\)

\(\Leftrightarrow-11⋮x+4\)

\(\Leftrightarrow x+4\in\left\{1;-1;11;-11\right\}\)

hay \(x\in\left\{-3;-5;7;-15\right\}\)

Alo, sugeni two wai phem. Si ga no, you woo be the me that nas te, ai gi da

a) x + 18 = 25

=> x       = 25 - 18

=> x       = 7

b) x + 18 = 6 - 2x

=> x + 2x = 6 - 18

=> 3x       = -12

=> x         = -12 : 3

=> x         = -4

Chúc bn học tốt^^

Bài 1 :
a, x + 18 = 25

x = 25 - 18

x = 7 . Vậy x = 7

b, x + 18 = 6-2x

18 = 6-2x-x

18 - 6 = -2x - x 

12 = -3x

x = 12 : (-3)
x = -4

Vậy x = -4

Đúng tích mk nha!!