a) x - 3,22 = -8,19;

x = -8.19 + 3.22;

x = -4.97;

б) 2 8/15 + у = - 1 7/10;

y = -1 7/10 - 2 8/15;

y = -17/10 - 38/15;

y = -52/30 - 76/30;

y = -128/30;

y = -4 4/15.