it's pretty easy.

Edit Answers
12345678910111213
Across
  1. 3. a line
  2. 8. Ax+By=C
  3. 10. 3
  4. 11. 2
  5. 12. the very tiny number
  6. 13. 1
Down
  1. 1. 4+
  2. 2. Degree of 2
  3. 4. Degree of 3
  4. 5. One number in the equation
  5. 6. Degree of 4
  6. 7. First number in Standard form
  7. 9. The biggest tiny number