Algebra puzzle

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Across
  1. 1. the total amount given from the addition of two numbers
  2. 3. the result when subtracting one number from another
  3. 4. a quantity representing the power to which a given number or expression is to be rasied
  4. 7. the result obtained by dividing
  5. 8. The letter in the equation that represents and unknown number
  6. 9. when multiplying and expression with two or more number's
Down
  1. 1. The simplest representation of an object equation
  2. 2. The law relating the operation of multiplication and addition
  3. 5. the product from which a number is multiplied by itself
  4. 6. to represent it in the least complicated form possible