a) |2x - 3| = 6
<=> \(\left[ \begin{array}{l}2x-3=6\\2x - 3 = -6\end{array} \right.\)
<=> \(\left[ \begin{array}{l}2x= 9\\2x = -3\end{array} \right.\)
<=> \(\left[ \begin{array}{l}x=4,5\\x = -1,5\end{array} \right.\)
Vậy...
b) 2|3x+1| = 5
<=>|3x+1| =2,5
<=> \(\left[ \begin{array}{l}3x+1 = 2,5\\3x+1 = -2,5\end{array} \right.\)
<=> \(\left[ \begin{array}{l}3x = 1,5\\3x = -3,5\end{array} \right.\)
<=> \(\left[ \begin{array}{l}x=1,5\\x = -7/6\end{array} \right.\)
Vậy...
c) 7,5-3|5-2x| = -4,5
<=> 3|5-2x| = 12
<=>|5 - 2x| = 4
<=> \(\left[ \begin{array}{l}5-2x = 4\\5-2x = -4\end{array} \right.\)
<=> \(\left[ \begin{array}{l}2x = 1\\2x = 9\end{array} \right.\)
<=> \(\left[ \begin{array}{l}x = 0,5\\x = 4,5\end{array} \right.\)
d) |3x-1| = |x+3|
<=> \(\left[ \begin{array}{l}3x-1 = x+3\\3x - 1 = -x - 3\end{array} \right.\)
<=> \(\left[ \begin{array}{l}2x = 4\\4x = -2\end{array} \right.\)
<=> \(\left[ \begin{array}{l}x = 2\\x = -0,5\end{array} \right.\)
Vậy...
