a.\(\left|3x\right|=x+7\)
b.\(\left|-4x\right|=-2x+11\)
c.\(\left|5x\right|=3x+4\)
d.\(\left|3x\right|-x-4=0\)
e.\(|9-\left|-5x\right|+2x=0\)
f.\(\left|x-9\right|=2x+5\)
g.\(\left|6-x\right|=2x-3\)
h.\(\left|2x+1\right|=6x+2\)
i.\(\left|4x\right|=2x+12\)
j.\(\left|4-x\right|=2x+1\)
a.\(|3x|=x+7\)
Nếu \(3x\ge0\Leftrightarrow x\ge0\).Khi đó ta có:
\(3x=x+7\)
\(\Leftrightarrow2x=7\)
\(\Leftrightarrow x=\dfrac{7}{2}=3,5\)
Nếu \(3x< 0\Leftrightarrow x< 0\).Khi đó ta có:
\(-3x=x+7\)
\(\Leftrightarrow-4x=7\)
\(\Leftrightarrow x=-\dfrac{7}{4}\)