Expressions Unite by Noah Giles (the best)

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Across
  1. 2. Order Changes
  2. 6. Cancels out
  3. 8. Any # of terms
  4. 9. a monomial seperated by plus or minus signs
Down
  1. 1. has both adding and multiplication in the same example
  2. 3. 1 term
  3. 4. Get what you started with
  4. 5. 2 terms
  5. 7. parentheses change