1. Geometry Quadrilaterals

2. Geometry: Plane Shapes quadrilateral: any closed, four-sided shape

3. Geometry: Plane Shapes parallelogram: any quadrilateral with two pairs of parallel sides.

4. Geometry: Plane Shapes rectangle: a parallelogram with four right angles.

5. Geometry: Plane Shapes rhombus: a parallelogram with four equal sides.

6. Geometry: Plane Shapes square: a parallelogram with four right angles and four equal sides.

7. Geometry: Plane Shapes trapezoid: a quadrilateral with only one pair of parallel sides.

8. Geometry: Plane Shapes quadrilateral: any closed, four-sided shape

9. Geometry: Plane Shapes parallelogram: any quadrilateral with two pairs of parallel sides.

10. Geometry: Plane Shapes rectangle: a parallelogram with four right angles.

11. Geometry: Plane Shapes rhombus: a parallelogram with four equal sides.

12. Geometry: Plane Shapes square: a parallelogram with four right angles and four equal sides.

13. Geometry: Plane Shapes trapezoid: a quadrilateral with only one pair of parallel sides.

15. Geometry Triangles

16. Geometry: Triangles equilateral triangle: a triangle with 3 equal sides.

17. Geometry: Triangles isosceles triangle: a triangle with 2 equal sides.

18. Geometry: Triangles scalene triangle: a triangle with 0 equal sides.

19. Geometry: Triangles right triangle: a triangle with 1 right angle.

20. Geometry: Triangles obtuse triangle: a triangle with 1 obtuse angle.

21. Geometry: Triangles acute triangle: a triangle with 3 acute angle.