Geometry Puzzle

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Across
  1. 2. A quadrilateral with four equal sides and angles, not a square. It is not rectilinear because it does not have right angles.
  2. 3. Lines are called __________________ lines when they cross each other at any point. Perpendicular lines could also be classified under this label.
  3. 5. A quadrilateral with one pair of parallel sides and one pair of nonparallel sides. It is a convex polygon because all of its angles measure less than 180°.
  4. 6. A triangle with no equal sides is called a(n) ________________ triangle. Though the angles add up to 180°, none of them are equal to each other.
  5. 12. A quadrilateral with two pairs of parallel lines. This figure is rectilinear because it contains all straight lines and right angles.
  6. 14. A part of a line. It is different from a line because it has a definite, measurable length.
  7. 16. An infinite, straight figure with no width or depth. It differs from a line segment in that it has an infinite length.
  8. 17. A five-sided polygon. Each interior angle is 108°.
  9. 19. An angle between 0 and 90° is called a(n) _______ angle. It does not have to be a part of a polygon to receive this label.
  10. 20. Lines are called ___________________ when their point of intersection creates 90-degree angles. These lines can be marked with this symbol: ⟂
  11. 23. Any line segment between two points on a circle is called a(n) _______. If infinitely extended, it would be considered a secant line.
  12. 25. An eight-sided polygon. Each interior angle measures 135°.
  13. 26. A triangle with two equal sides is called a(n) ________________ triangle. The triangle also has two equal angles.
Down
  1. 1. A four-sided polygon. It has four vertices and four straight sides.
  2. 4. An six-sided polygon. Each interior angle measures 120°.
  3. 6. A quadrilateral with equal-length sides. All angles are right angles.
  4. 7. A line segment from one edge of the circle to the other that passes through the center. It is the longest chord of the circle.
  5. 8. 90-degree angles are called ______ angles. They are marked by this symbol: ∟
  6. 9. A line segment that starts at a point and continues in one direction. It is considered to be a half-infinite line.
  7. 10. A parallelogram with four 90-degree angles. It is not a square.
  8. 11. Also called a corner. This is where two lines, meet each other at a point.
  9. 13. A line segment from the center of the circle to the edge. The line segment can end at any point on the circumference of the circle.
  10. 15. A triangle with three equal sides is called a(n) ________________ triangle. Each angle is also equal, measuring 60°.
  11. 18. A round figure with equal radii all the way around. Its perimeter is called the circumference.
  12. 20. Line segments that never intersect. They are represented by this symbol: ∥
  13. 21. A specific location in space with no length, width, or depth. This figure is represented by a dot. (.)
  14. 22. A curve is said to be _________ when its starting and ending points are indistinguishable. One example of a _________ figure is a circle.
  15. 24. An angle between 90 and 180 degrees is called a(n) _______ angle. A hexagon has all ________ angles.