Ответ:

  1. \(5a+27a-a=(5+27-1)a=31a\).
  2. \(12b-17b-b=(12-17-1)b=-6b\).
  3. \(6x-13x-14+26=-7x+12\).
  4. \(-y-10y-8+17=-11y+9\).
  5. \((13-2)a+(2-1)b=11a+b\).
  6. \((-5.1-4.9)a+(-4+1)b=-10a-3b\).
  7. \((41-58)x+(6-1)y=-17x+5y\).
  8. \((7.5-8.5)x+(1-3.5)y=-x-2.5y\).
  9. \((8-7)x+(-6-2)y=x-8y\).
  10. \((3.5-0.7)b+(-2.4-0.6)c=2.8b-3c\).
  11. \((27-16)p+(14-3)q=11p+11q\).
  12. \((1.6-2.8)a+(4-7.5)x=-1.2a-3.5x\).