Question

|2x|-|-2.5|=|-7.5|

 

Answer 1

\(\left|2x\right|-\left|-2,5\right|=\left|-7,5\right|\)

\(\left|2x\right|-2,5=7,5\)

|2x| = 7,5 + 2,5

|2x | = 10

TH1: 2x = 10

x=5

TH2: 2x= -10

x = -5

KL: x = 5 hoặc x = -5

Answer 2

\(\left|2x\right|-\left|-2\cdot5\right|=\left|-7\cdot5\right|\)

\(\Rightarrow\left|2x\right|-\left|-10\right|=\left|-35\right|\)

\(\Rightarrow\left|2x\right|-10=35\)

\(\Rightarrow\left|2x\right|=45\)

\(\Rightarrow\orbr{\begin{cases}2x=45\\2x=-45\end{cases}}\)

\(\Rightarrow\orbr{\begin{cases}x=22,5\\x=-22,5\end{cases}}\)