1)
[tex]-1.4 - (5.7 - x) = -3.6[/tex]
[tex]-1.4 - 5.7 + x = -3.6[/tex]
[tex]-7.1 + x = -3.6[/tex]
[tex]x = -3.6 + 7.1[/tex]
[tex]x = 3.5[/tex]

2)
[tex]2 \frac{5}{6} - (-y + 7) = -8 \frac{1}{2}[/tex]
[tex]\frac{17}{6} + y - 7 = -17 \frac{1}{2}[/tex]
[tex]\frac{17}{6} + y - 7 = - \frac{35}{2}[/tex]
[tex]\frac{17}{6} + y - \frac{42}{6} = - \frac{35}{2}[/tex]
[tex]y - \frac{25}{6} = - \frac{35}{2}[/tex]
[tex]y = - \frac{35}{2} + \frac{25}{6}[/tex]
[tex]y = - \frac{70}{4} + \frac{25}{6}[/tex]
[tex]y = - \frac{105}{12} + \frac{50}{12}[/tex]
[tex]y = - \frac{55}{12}[/tex]