a) 2/3x - 1/2x = (-7/12). 1$\frac{2}{5}$
⇔ 1/6x = -49/60
⇔ x= -49/10
b) (1/5 - 3/2x)² = 9/4
⇔ \(\left[ \begin{array}{l}1/5-3/2x=3/2\\1/5-3/2x=-3/2\end{array} \right.\)
⇔ \(\left[ \begin{array}{l}3/2x=-13/10\\3/2x=17/10\end{array} \right.\)
⇔ \(\left[ \begin{array}{l}x=-13/15\\x=17/15\end{array} \right.\)
c) (1,25 - 4/5x)³ = -125
⇔ 1,25 - 4/5x = -5
⇔ 4/5x = 25/4
⇔ x = 125/16
d) $2^{x}$ + $2^{x+4}$=544
⇔ $2^{x}$ + $2^{x}$.$2^{4}$ =544
⇔ $2^{x}$(1 + $2^{4}$) = 544
⇔ $2^{x}$ . 17 = 544
⇔ $2^{x}$ = 32
⇔ $2^{x}$ = $2^{5}$
⇒ x = 5
