3D Shapes

3D Shapes

1. Oblique Shapes

   • sides not at right angles to the base

2. a 3d solid has length, width, depth

3. Non-Convex (concave)= 1 diagonal is outside the solid.

   • Convex= all diagonals are inside the shape.

4. Euler's Rule

   • Face+Vertices-Edges=2
   • Euler- mathematician who found relationship between the f,v,e of pyramids and prisms

5. Congruent= exact same size and shape

6. Apex= point at top of pyramids

7. Plane= flat

8. Polyhedra= solid with flat surfaces

9. Prism, Pyramids

10. Parallelograms= 4 sided flat shape with 2 sides parallel

11. Perpindicular Lines= 2 lines that cross at right angles

12. Skew Lines= 2 lines, don't intersect & r not parallel

13. Parallel lines= same distance apart, never meet eachother

14. Shape & Their Sides

    • Triangle- 3
    • Hexagon- 6
    • Octagon- 8
    • Nonagon- 9
    • Pentagon- 5
    • Heptagon- 7
    • Decagon- 10
    • Undecagon- 11
    • Quadrilateral- 4
    • icosahedron- 20
    • Dodecahedron- 12

15. Truncated Tetrahedron

    • bottom half of a triangular pyramid

16. Faces- individual surface of a solid

    • vertex- point where to or more straight lines meet
    • Edge- line that joins 2 vertices

17. Platonic Solids

    • 5 platonic solids
      • icosahedron= 20 triangle faces
      • dodecahedron= 12 pentagon faces
      • Cube= 6 square faces
      • Tetrahedron (triangle pyramid)= 4 faces
      • octahedron= 8 triangle faces
    • Each face is regular.