Matching addition puzzle

123456
Across
  1. 1. 6 + 4
  2. 2. 5 + 11
  3. 4. 8 + 5
  4. 5. 7 + 2
  5. 6. 12 + 3
Down
  1. 1. 4 + 9
  2. 2. 10 + 7
  3. 3. 3 + 6