Triangles puzzle

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Across
  1. 3. The figure formed by two rays with a common endpoint.
  2. 6. A triangle with two equal sides.
  3. 11. A triangle with all sides equal.
  4. 12. A line segment joining a vertex to the midpoint of the opposite side.
Down
  1. 1. A triangle with one angle greater than 90°.
  2. 2. The point where two sides meet.
  3. 4. A triangle with one angle equal to 90°.
  4. 5. The longest side of a right triangle.
  5. 7. One of the three line segments of a triangle.
  6. 8. A triangle with all angles less than 90°.
  7. 9. A triangle with all sides of different lengths.
  8. 10. A perpendicular line from a vertex to the opposite side.