a) \(3\left|x\right|-6=2-\left(-7\right)\)

\(\Leftrightarrow3\left|x\right|-6=2+7\)

\(\Leftrightarrow3\left|x\right|-6=9\)

\(\Leftrightarrow3\left|x\right|=9+6\)

\(\Leftrightarrow3\left|x\right|=15\)

\(\Leftrightarrow\left|x\right|=15:3\)

\(\Leftrightarrow\left|x\right|=5\)

\(\Rightarrow\left[{}\begin{matrix}x=5\\x=-5\end{matrix}\right.\)

Vậy \(x=5\) hoặc \(x=-5\)

b) Ta có:

\(x-1⋮2x+3\)

\(\Rightarrow2\left(x-1\right)⋮2x+3\)

\(\Rightarrow2x-2⋮2x+3\)

\(\Rightarrow\left(2x+3\right)-5⋮2x+3\)

\(\Rightarrow-5⋮2x+3\)

\(\Rightarrow2x+3\in U\left(5\right)=\left\{-1;1;-5;5\right\}\)

\(\Rightarrow\left\{{}\begin{matrix}2x+3=-1\Rightarrow x=-2\\2x+3=1\Rightarrow x=-1\\2x+3=-5\Rightarrow x=-4\\2x+3=5\Rightarrow x=1\end{matrix}\right.\)

Mà \(x\ge1\)

Vậy \(x=1\)

a) 10ⁿ  - 1 chia hết cho 9

10ⁿ - 1ⁿ = (10 - 1)ⁿ = 9ⁿ luôn chia hết cho 9

b) 10ⁿ + 8 = (10 + 8)ⁿ = 18ⁿ luôn chia hết cho 9

a) \(500+500+500=x\)

\(\Rightarrow1000+500=x\)

\(\Rightarrow1500=x\)

Vậy \(x=1500\)

b) \(x+x+x=15\)

\(\Rightarrow3x=15\)

\(\Rightarrow x=15:3\)

\(\Rightarrow x=5\)

Vậy \(x=5\)

c) \(50+50=x.50\)

\(\Rightarrow100=x.50\)

\(\Rightarrow x=100:50\)

\(\Rightarrow x=2\)

Vậy \(x=2\)

AI CHO 8 **** de tron 20 **** di T_T

Ta có: \(0,5\left(12\right)=\dfrac{512-5}{990}=\dfrac{507}{990}=\dfrac{169}{330}\)

Do đó: \(1,5\left(12\right)=1+0,5\left(12\right)=1+\dfrac{169}{330}=\dfrac{330}{330}+\dfrac{169}{330}=\dfrac{330+169}{330}=\dfrac{499}{330}\)

25%

Tick nha ban hien

a) -x+18-4x-64-16=-x-4x+18-64-16=-5x-62

b) x+36+4+2x+24=x+2x+36+4+24=3x+64

c) x-23+13+2x-17+57=x+2x-23+13-17+57=3x+29

Tick nha

Giống Nguyễn Mạnh Tuấn rùi

đơn giản biểu thức là sao