math puzzle2

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Across
  1. 2. A rate with a denominator of 1.
  2. 4. A value that measures distance and is always positive.
  3. 5. The replacement of the letters in an algebraic expression with known values
  4. 8. To find the value of a mathematical expression
  5. 9. If two ratios have the same value when simplified, then they are called this
Down
  1. 1. A triangle that has one 90º angle
  2. 3. The sum stays the same when the order of the addends is changed
  3. 4. A triangle with no angle measuring 90º or more.
  4. 6. less than 0.
  5. 7. the result of multiplication