Algebra puzzle

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Across
  1. 3. a two term expression
  2. 4. what you get after subtracting
  3. 7. the number above the fraction
  4. 9. any number of terms
  5. 10. terms that can't be simplified
  6. 14. an unknown number represented by a letter
Down
  1. 1. the end result of division
  2. 2. terms that can be simplified
  3. 4. the number under the fraction
  4. 5. the number that remains the same
  5. 6. a three term expression
  6. 8. what you get when you add
  7. 11. a single term
  8. 12. the amount of variables in a term
  9. 13. the end result of multiplication