HERON'S FORMULA

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Across
  1. 1. Number of books written by Heron.
  2. 5. Sum of all sides upon two.
  3. 7. Comparison of two or more quantities.
  4. 8. Great mathematician of 10 A.D.
  5. 9. Measure of an angle in an equilateral triangle.
Down
  1. 2. A triangle with all sides equal.
  2. 3. Another name of trapezoids.
  3. 4. Birthplace of Heron.
  4. 5. A triangle with three different sides.
  5. 6. Triangle with two equal sides.