ta có: 2x+1=10
2x+1=-10
nếu 2x+1=10
=>2x=9
x=9/2
nếu 2x+1=-10
2x=-11
x=-11/2
vậy x=9/2
or -11/2
2.|2x+1|=5
|2x+1|=5.2
|2x+1|=10
\(\Rightarrow\orbr{\begin{cases}2x+1=10\\2x+1=-10\end{cases}}\Rightarrow\orbr{\begin{cases}2x=9\\2x=-11\end{cases}}\Rightarrow\orbr{\begin{cases}x=\frac{9}{2}\\x=\frac{-11}{2}\end{cases}}\)
Vậy x=9/2 hoặc x=-11/2
2 . | 2x + 1 | = 5
=> | 2x + 1 | = \(\frac{5}{2}\)
=> \(\orbr{\begin{cases}2x+1=\frac{5}{2}\\2x+1=-\frac{5}{2}\end{cases}\Rightarrow\orbr{\begin{cases}2x=\frac{3}{2}\\2x=-\frac{7}{2}\end{cases}\Rightarrow}\orbr{\begin{cases}x=\frac{3}{4}\\x=-\frac{7}{4}\end{cases}}}\)
Vậy x = 3 / 4 hoặc x = - 7 / 4