Here are some, with number of triangular faces in brackets:
tetrahedron (4)
triangular bipyramid (6)
octahedron (8)
pentagonal bipyramid (10)
snub disphenoid (12)
triaugmented triangular prism (14)
gyroelongated square bipyramid (16).
There is also a 24 faced stellation for an octahedron.
Here are some, with number of triangular faces in brackets:
tetrahedron (4)
triangular bipyramid (6)
octahedron (8)
pentagonal bipyramid (10)
snub disphenoid (12)
triaugmented triangular prism (14)
gyroelongated square bipyramid (16).
There is also a 24 faced stellation for an octahedron.
Here are some, with number of triangular faces in brackets:
tetrahedron (4)
triangular bipyramid (6)
octahedron (8)
pentagonal bipyramid (10)
snub disphenoid (12)
triaugmented triangular prism (14)
gyroelongated square bipyramid (16).
There is also a 24 faced stellation for an octahedron.
Here are some, with number of triangular faces in brackets:
tetrahedron (4)
triangular bipyramid (6)
octahedron (8)
pentagonal bipyramid (10)
snub disphenoid (12)
triaugmented triangular prism (14)
gyroelongated square bipyramid (16).
There is also a 24 faced stellation for an octahedron.
An octahedron.
tetrahedron
What polyhedron has eight sides and all of the are equilateral triangle?
You're an octagon.
A regular octahedron.
Octohedron, or rhomboid.
A regular octahedron.
A regular octahedron.
Princess cut diamonds
pentagon
its a dedrehedron * * * * * Sadly, a dedrehedron does not exist. Fotunately, though, a regular octahedron does and it meets the specifications in the question.
that's easy its a triangle * * * * * That is such a nonsensical answer! A triangle is not even a polyhedron. The correct answer is an octahedron - two square based pyramids stuck together along their bases.