easy math

123456
Across
  1. 1. 18+4-15
  2. 3. 21-8-2
  3. 6. 10+5-7
Down
  1. 1. 32-25+8-12
  2. 2. 28-12-6
  3. 4. 19-27+12
  4. 5. 36-29+2