Math Riddle

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Across
  1. 2. is the time we multiplicate a number by itself
  2. 6. Part of Math we use letters and numbers
  3. 8. Part of Mathematics that study events
  4. 9. Operations agains to sum
Down
  1. 1. Theorem in Geometry
  2. 2. you can separate the operations to associate
  3. 3. Operation where we sum values
  4. 4. instrument to get the measure of the angles.
  5. 5. a value that can be expressed by an X
  6. 7. value that never changes