Lines and Angles ,Triangles

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Across
  1. 3. Sum of angles is 90 degree
  2. 6. corresponding angles between parallel lines
  3. 7. No end points
  4. 8. line segment joining the midpoint of side to the vertex of triangle
Down
  1. 1. Sum of angles is 180 degree
  2. 2. segment two end points
  3. 4. One of angle is 90 degree
  4. 5. perpendicular drawn from vertex to the opposite side of triangle