Question

3. Tìm x, biết

a) \(\left|x-1\right|\)=5

b) \(\left|x-0,5\right|\)=2,4

c) 2\(\left|3x-1\right|\)-1=6

Giúp mình với

Answer 1

a)\(\left|x-1\right|=5\Leftrightarrow\left[{}\begin{matrix}x-1=5\\x-1=-5\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=6\\x=-4\end{matrix}\right.\)

b) \(\left|x-0,5\right|=2,4\Leftrightarrow\left[{}\begin{matrix}x-0,5=2,4\\x-0,5=-2,4\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=2,9\\x=-1,9\end{matrix}\right.\)

c) \(2\left|3x-1\right|-1=6\Leftrightarrow2\left|3x-1\right|=7\)

c nhân -1 hay là trừ 1