Bạn tham khảo:
a, $-2( 2x - 8 ) + 3( 4 - 2x ) = -72 - 5( 3x - 7 )$
$⇔ -4x + 16 + 12 - 6x = -72 - 15x + 35$
$⇔ -4x - 6x + 15x = -72 + 35 - 16 - 12$
$⇔ 5x = -65$
$⇔ x = -13$
b, $3.| 2x.2 - 7 | = 33$
$⇔ | 4x - 7 | = 11$
$⇔$ \(\left[ \begin{array}{l}4x-7=11\\4x-7=-11\end{array} \right.\)
$⇔$ \(\left[ \begin{array}{l}x=\dfrac{9}{2}\\x=-1\end{array} \right.\)