a, x : 12 = 27

=> x = 27.12 = 324

Vậy x = 324

b, 1414 : x = 14

=> x = 1414 : 14 = 101

Vậy  x = 101

c, 5x : 12 = 0

=> 5x = 0

=> x = 0.

Vậy x = 0

d, 0 : x = 0

∀ x ∈ ¥, x≠0

\(\Leftrightarrow x\in\left\{2;-2\right\}\)

\(\Rightarrow\left(x-2\right)\left(x+2\right)=0\\ \Rightarrow\left[{}\begin{matrix}x=2\\x=-2\end{matrix}\right.\)

(5x - 10) . (6x + 12) = 0 

=>(5x - 10) = 0 hoặc (6x + 12) = 0 

 * TH1: (5x - 10) = 0           * TH2: (6x + 12) = 0 

             =>x = 2                             => x = -2

                     Vậy x=2 hoặc x = -2

Ta có: 5x(x-3)+4x-12=0

=> 5x(x-3)+4(x-3)=0

=> (5x+4).(x-3)=0

\(\Rightarrow\orbr{\begin{cases}5x+4=0\Rightarrow5x=-4\Rightarrow x=-\frac{4}{5}\\x-3=0\Rightarrow x=3\end{cases}.}\)

Vậy x=3; -4/5

5x(x-3)+4(x-3)=0

(x-3)(5x+4)=0

=>\(\hept{\begin{cases}x-3=0\\5x+4=0\end{cases}}\)=>\(\hept{\begin{cases}x=3\\x=-\frac{4}{5}\end{cases}}\)

\(a,12\left(x-1\right)=0\\ x-1=0\\ x=1\\ b,45+5\left(x-3\right)=70\\ 5\left(x-3\right)=25\\ x-3=5\\ x=8\\ c,3.x-18:2=12\\ 3.x-9=12\\ 3.x=21\\ x=7\)

12(x-1)=0

     (x-1)=0:12

      x-1=0

      x=0+1

      x= 1

Vậy x= 1

12 ( x - 1 ) = 0
       x - 1   = 0 : 12
       x - 1   = 0
=>   x        = 1

5x+45-12=0
5x+45=12
5x=12-45
5x=-33
x=-33/5=>x=-6,6
Tick cho mình nha Nguyễn Quốc Huy
 

x=125

dung 100phan 100

\(\Leftrightarrow30x^2-72x+55x-132-42x+66=0\\ \Leftrightarrow30x^2-59x-66=0\\ \Delta=3481-4\cdot\left(-66\right)\cdot30=11401\\ \Leftrightarrow\left[{}\begin{matrix}x=\dfrac{59-\sqrt{11401}}{60}\\x=\dfrac{59+\sqrt{11401}}{60}\end{matrix}\right.\)

(5x+75)(12-6x)=0

=> 5x+75=0 hoặc 12-6x=0

* 5x+75=0=>x=-15

*12-6x=0=>x=2

Vậy x=-15 hoặc x=2