geometry tic-tac-toe

2. a 180 degree angle
4. and angle with a measure less than 90 degrees
5. a figure with congruent sides and four right angles; a square is always a rhombus; all squares are considered rectangles
8. a polygon is convex if there are no "dents" or indentations in it.
9. a triangle with one obtuse angle
13. a triangle with three acute angles
14. a polygon with four sides and four angles
15. a 90 degree angle
16. a triangle with a right angle (90 degrees)
17. a 2-dimensional figure formed by three or more line segments (sides) that meet only at their endpoints (vertices) to make a closed path; sides may not cross one another
18. a triangle with all three sides equal in length, each angle of an equilateral triangle measures 60 degrees
19. a triangle with two sides equal in length

1. a triangle with no sides equal in length
3. a polygon in which all sides are the same length and all angles have the same measure
6. A rhombus is a quadrilateral whose four sides are congruent; it has two pairs if parallel sides; squares are a type of rhombus with congruent angles
7. an angle with a measure more than 90 degrees
8. a polygon with an angle measuring more than 180 degrees; concave polygons look like they are collapsed or have one or more angles "dented" in.
10. a quadrilateral with at least one pair of paralell sides
11. a quadrilateral with two pairs of parallel sides; opposite sides have the same length and opposite angles have the same measure; all rectangles are parallelograms but not all parallelograms are rectangles because parallelograms do not necessarily have right angles
12. a figure with four sides and four right angles; opposite sides are parallel and congruent, a rectangle is sometimes a trapezoid; a rectangle is sometimes a square.