x = 4

\(x+\left|-3\right|=-\left|-7\right|\)

\(x+3=-7\)

\(x=-7-3\)

\(x=-10\)

X × 12,3 + 0,4 = 148

X x 12,3 = 148- 0,4

X x 12,3 = 147,6

x= 147,6 : 12,3

x = 12

=>x-4368=13936

hay x=18304

Ta có: x(1+30%)=-1,31

  ⇒        \(\dfrac{13}{10}\)x         =-1,31

  ⇒         x             =-1,31 : \(\dfrac{13}{10}\)

  ⇒         x             = -\(\dfrac{131}{130}\)

x + 30% x = -1,31

\(x+\dfrac{30}{100}x=-1,31\)

x+0,3x=-1,31

x.(0,3+1)=-1,31

x.1,3=-1,31

\(x=\dfrac{-1,31}{1,3}\)

\(x=-\dfrac{131}{130}\)

\(x^2+x=12\)

\(\Rightarrow x^2+x-12=0\)

\(\Rightarrow x\left(x-3\right)+4\left(x-3\right)=0\Rightarrow\left(x-3\right)\left(x+4\right)=0\)

\(\Rightarrow\left[{}\begin{matrix}x=3\\x=-4\end{matrix}\right.\)

\(x : 11 - 145 = 526\)

\(x : 11 = 526 + 145\)

\(x : 11 = 671\)

\(x = 671 \) x \(11\)

\(x = 7381\)

Vậy \(x=7381\)

x:11 = 671

x = 61

\(\Rightarrow x:11=526-145\)

\(\Rightarrow x:11=381\)

\(\Rightarrow x=381.11\)

\(\Rightarrow x=7381\)

x : 2,3 -12,4 =0,94

x : 2,3 = 0,94 + 12,4

x : 2,3 = 13,4

x= 13,4 . 2,3

x= 30,682

x : 2,3 - 12,4 = 0,94

x : 2,3 = 0,94 + 12,4

x : 2,3 = 13,34

        x = 13,34 x 2,3

       x = 30,682.

Chúc học tốt!

x : 2,3 - 12,4 = 0,94

=>x:2,3         =0,94 +12,4

=>x: 2,3        =13,34

=>x               =13,34 . 2,3

=>x               =30,682

\(x-\dfrac{4}{12}=-\dfrac{5}{6}\)

⇔\(x-\dfrac{1}{3}=-\dfrac{5}{6}\)

⇔\(x=-\dfrac{1}{2}\)

\(\Leftrightarrow x=-\dfrac{1}{2}\)

=>(x-4).6=12.(-5)

=>6x-24=-60

=>6x=-36

=x=-6

\(x^{15}=x\)

\(\Rightarrow x^{15}-x=0\)

\(\Rightarrow x.\left(x^{14}-1\right)=0\)

\(\Rightarrow\orbr{\begin{cases}x=0\\x^{14}-1=0\end{cases}}\)

\(\Rightarrow\orbr{\begin{cases}x=0\\x^{14}=0+1=1\end{cases}}\)

\(\Rightarrow\orbr{\begin{cases}x=0\\x=1\end{cases}}\)

Ta có : x : x¹⁵ = x 

<=> x = x¹⁶

=> x = 1 ; 0 

8.75x + 10 = 30 + 1.26x

8.49x + 10 = 30 

8 . 49x = 30 - 10

8 . 49x = 20

49x = 20 : 8

49x = 2.5

x = 2.5 : 49

x = 5/98

xin lỗi;số 1.26x phải la136x mình chép nhầm đề