Given that a polyhedron has 12 edges and 6 vertices, then the polyhedron is () a pentahedron B hexahedron C octahedron D12

Given that a polyhedron has 12 edges and 6 vertices, then the polyhedron is () a pentahedron B hexahedron C octahedron D12

The answer is C octahedron
Because: in a polyhedron, there is a relationship between the number of vertices V, the number of faces F and the number of edges e of a simple polyhedron
V+F-E=2
This formula is called Euler's formula. It describes the special rules of vertex number, face number and edge number of simple polyhedron

There is a polyhedron with 36 vertices and 20 faces. How many faces is this polyhedron

This is an eighteen prism. It has 54 edges

The number of faces of a polyhedron with 12 edges and 6 vertices is ()

The number of faces of a polyhedron with 12 edges and 6 vertices is (8)

How to check the simple equation
3+X=5.4 X-6=7.6

3+X=5.4
X=5.4-3
X=2.4
Test: substitute x = 2.4 into the original equation
Left = 3 + 2.4 = 5.4
Right = 5.4
Left = right
So x = 2.4 is the solution of the original equation
X-6 = 7.6 (similarly)

Equation checking
3-9（8-x）=-6（15-2x）
x=7

3-9（8-x）=-6（15-2x）
Substituting x = 7 into the original equation
Left = 3-9 × (8-7) = 3-9 × 1 = - 6
Right = - 6 × (15-2 × 7) = - 6 × 1 = - 6
Left = right
So x = 7 is the solution of the original equation

Checking calculation of equation

If the two sides are equal, it is called checking calculation

How to write simple equation for checking calculation
1.x+0.3=1.8
2.x-1.5=4
3.5*x=1.5
4.x/1.1=3
Answer and write the check

I'm learning now, all from books ~ 1. X + 0.3 = 1.8, x = 1.8-0.3, x = 1.5 test: the left side of the equation = x + 0.3 = 1.5 + 0.3 = 1.8 = the right side of the equation, so x = 1.5 is the solution of the equation 2. X-1.5 = 4, x = 4 + 1.5, x = 5.5 test: the left side of the equation = x-1.5 = 5.5-1.5 = 4 = the right side of the equation, so x = 5.5

Simple equation exercises

x+2.4x=5.1

How to solve the equation 60% X - 35% x = 125

60%x -35%x=125
0.6x-0.35x=125
0.25x=125
x=125/0.25
x=500

How to calculate the equation 42x + 35 (6-x) = 231?

42x+35（6-x）=231
42x+210-35x=231
42x-35x=231-210
7x=21
x=21/7
x=3