Addition vs Subtraction

12345678910
Across
  1. 5. 32424-11100
  2. 6. 1211321518700000+89149
  3. 9. 20000000+11216145
  4. 10. 294262631629-101111111111
Down
  1. 1. 131520151829115+8x9-72
  2. 2. 29302293422929-10101111111110
  3. 3. 12007+11111
  4. 4. 19111205215184+90-9x10
  5. 7. 20649-10100
  6. 8. 80x80+2920