Answer:
Step-by-step explanation:
Let
V
be the number of vertices of a polyhedron,
F
the number of faces of that polyhedron, and
E
be the number of edges. The quantity
χ
=
V
−
E
+
F
is called the Euler characteristic (of a polyhedron). In the case of convex polyhedra,
χ
=
2
.
Consider, for example, a tetrahedron (which is the simplest solid). It has 4 faces,
1
2
(
4
)
(
3
)
=
6
edges, and
1
3
(
4
)
(
3
)
=
4
vertices. Thus we have
V
−
E
+
F
=
4
−
6
+
4
=
2
.
Euler's formula holds for all Platonic solids (tetrahedron, cube, octahedron, dodecahedron, and icosahedron). Since a cube and an octahedron are dual polyhedra (each is formed by connecting the centers of the faces of the other), their
V
and
F
values are equal to the
F
an
V
values of the other. (The same is true for the dodecahedron and icosahedron).
The common ratio is (B)1/4
Answer:
x = 5 - 3y and y = - 7/3 + 5x/3
Step-by-step explanation:
uh -
I don't think that's what your looking for
Answer:
AB
Step-by-step explanation:
The diameter is the line that goes from one side of the circle to the other passing through the center
The diameter is AB
It could also be named BA
Answer:
∠2 = 78°
Step-by-step explanation:
Angle of a straight line is 180°.
So, that would mean ∠1 + ∠2 = 180°.
⇒ ∠2 = 180° - ∠1
⇒ ∠2 = 180° - 102°
⇒ ∠2 = 78°
Hence, the answer.
