a,$|\frac{-2}{5}+|$$|\frac{1}{2}-$$2x|$=$(-1^2)$
$\frac{2}{5}+$$\frac{1}{2}$-$2x=$$-1^2$
$\frac{1}{2}-$$2x$=$\frac{2}{5}+$ $-1^2$
$\frac{1}{2}-$$2x$=$\frac{-1}{10}$
$2x=$$\frac{1}{2}$-$\frac{1}{10}$
$2x$=$\frac{2}{5}$
$x=$$\frac{2}{5}$:$2$$
$x=$$\frac{1}{5}$
b,|$3x+$$\frac{1}{2}$|$-\frac{3}{4}$= $\frac{7}{3}$
|$3x+$$\frac{1}{2}$|=$$\frac{37}{12}$
$3x+$$\frac{1}{2}$$=±$\frac{37}{12}$
⇒$3x$=$\frac{31}{12}$
⇒$3x=$$\frac{-43}{12}$
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