а) \( -2x + 16 = 5x + 30 \)

\( 16 - 30 = 5x + 2x \)

\( -14 = 7x \)

\( x = \frac{-14}{7} = -2 \)

б) \( 11m - 7 = -22 + 5m \)

\( 11m - 5m = -22 + 7 \)

\( 6m = -15 \)

\( m = \frac{-15}{6} = -2,5 \)

в) \( 2,8 - 3,2a = -4,8 - 5,1a \)

\( 5,1a - 3,2a = -4,8 - 2,8 \)

\( 1,9a = -7,6 \)

\( a = \frac{-7,6}{1,9} = -4 \)

г) \( 0,893x - 6,54 = 0,894x - 3,78 \)

\( 0,893x - 0,894x = -3,78 + 6,54 \)

\( -0,001x = 2,76 \)

\( x = \frac{2,76}{-0,001} = -2760 \)

д) \( 3\frac{1}{4}x - 4\frac{5}{7} = 3\frac{5}{12}x - 3\frac{3}{14} \)

\( \frac{13}{4}x - \frac{33}{7} = \frac{41}{12}x - \frac{45}{14} \)

\( \frac{13}{4}x - \frac{41}{12}x = \frac{33}{7} - \frac{45}{14} \)

Приведём к общим знаменателям:

\( \frac{39}{12}x - \frac{41}{12}x = \frac{66}{14} - \frac{45}{14} \)

\( -\frac{2}{12}x = \frac{21}{14} \)

\( -\frac{1}{6}x = \frac{3}{2} \)

\( x = \frac{3}{2} \cdot (-6) = -9 \)

е) \( \frac{5}{12}y - \frac{7}{9}y = 10\frac{5}{12} - 3y \)

\( \frac{5}{12}y - \frac{7}{9}y + 3y = 10\frac{5}{12} \)

\( \frac{5}{12}y - \frac{7}{9}y + \frac{36}{12}y = \frac{125}{12} \)

Приведём к общему знаменателю 36:

\( \frac{15}{36}y - \frac{28}{36}y + \frac{108}{36}y = \frac{125}{12} \)

\( \frac{15 - 28 + 108}{36}y = \frac{125}{12} \)

\( \frac{95}{36}y = \frac{125}{12} \)

\( y = \frac{125}{12} \cdot \frac{36}{95} = \frac{125}{1} \cdot \frac{3}{95} = \frac{25}{1} \cdot \frac{3}{19} = \frac{75}{19} \)

Ответ: а) \( x = -2 \); б) \( m = -2,5 \); в) \( a = -4 \); г) \( x = -2760 \); д) \( x = -9 \); е) \( y = \frac{75}{19} \)

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