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Решите задачу:

$\frac{1}{2}-\frac{8}{5}x=\frac{9}{2}-3x$
$\frac{1}{2}-\frac{9}{2}=\frac{8}{5}x-3x$
$-\frac{8}{2}=-\frac{7}{5}x$
$-\frac{40}{10}=-\frac{14}{10}x$
$-4=\frac{7}{5}x$
$x=4:\frac{7}{5}=4*\frac{5}{7}=\frac{20}{7}=2\frac{6}{7}$

$2\frac{1}{3}x+1\frac{1}{2}=2\frac{1}{3}+1\frac{2}{3}x$
$2\frac{1}{3}x-1\frac{2}{3}x=2\frac{1}{3}-1\frac{1}{2}$
$\frac{2}{3}x=\frac{5}{6}$
$\frac{4}{6}x=\frac{5}{6};x=\frac{5}{6}:\frac{4}{6}=\frac{5}{6}*\frac{6}{4}=\frac{30}{24}=\frac{15}{12}=\frac{5}{4}=1.25$