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It is an arbitrary concept defined by Plato. actually the original 5 were different than the modern five, which were used by art instructors as Perspective props- they are: Sphere, Cube, Cone, Cylinder, and Pyramid! note the last one. somewhat oddly the ancient Egyptians did not draw in perspective- though they could not avoid the three dimensional look with statues, etc. That"s another story.
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What do the platonic solids look like?
The Platonic solids in modern Euclidean geometry are five regular polyhedra. These are three-dimensional objects that are bounded by regular polygonal faces. They are: Tetrahedron (or triangular pyramid): 4 triangular faces; Hexahedron (cube): 6 square faces; Octahedron: 8 triangular faces; Dodecahedron: 12 pentagonal faces; Icosahedron: 20 triangular faces. See link for more.
Why can t there be more then 5 platonic solids?
First, consider that at each vertex (point) at least three faces must come together, for if only two came together they would collapse against one another and we would not get a solid. Second, observe that the sum of the interior angles of the faces meeting at each vertex must be less than 360°, for otherwise they would not all fit together.
What is a platonic solid and how many are there and what are their names?
A Platonic solid is the 3-D shape equivalent of a polygon: it is a three dimensional figure whose sides are congruent, regular polygons, with identical vertices. Unlike the 2-dimensional case (in which there are infinitely many polygons) there are only 5 Platonic solids: * The tetrahedron, which has 4 triangular sides. * The cube (or hexahedron), which has 6 square sides. * The octahedron, which has 8 triangular sides. * The dodecahedron, which has 12 pentagonal sides. * The icosahedron, which has 20 triangular sides. Here is how the 5 Platonic solids were found, and how we know there aren't any more: Think about the sum of the angles at a vertex (by the definition of a Platonic solid, all vertices are identical). In the plane, angles around a vertex add up to 360 degrees, but we don't want the vertex to lie flat - otherwise, we'd end up with a huge flat sheet instead of a polyhedron. We also want at least 3 polygons around a vertex, because otherwise the result will become a flat figure without volume. If the sides are triangles, we can have 3 triangles around a vertex (getting the tetrahedron), 4 triangles around a vertex (getting the octahedron), or 5 triangles around a vertex (getting the icosahedron). We can't have 6 or more, because then the sum of angles wouldn't be less than 360. If the sides are squares, we can have 3 squares around a vertex, getting the cube. 4 squares around a vertex would mean the sum of angles is 360, and 5 or more is even more impossible. Finally, we can take 3 pentagons around a vertex, getting the dodecahedron; more pentagons will give us an angle sum of over 360. We can't use any shapes with more than 6 sides, because their angles are larger and we can't even fit 3 around a vertex. Even 3 hexagons will give an angle sum of 360 degrees, and anything more than that is even worse.
Five hundred is how much more than three hundred ninety-five?
500 - 395 = 105
What is two more than the total of a number and five?
two more than the total of a number and five = (x + 5) +2Let x = a numbertotal of a number and five = x + 5two more than = +2thus,two more than the total of a number and five = (x + 5) +2
