Assuming regular octagons, squares.
They may have no lines of symmetry or they may have some - it all depends upon the shape of the irregular octagon. Only regular octagons have 8 lines of symmetry.
-- All regular (equilateral) triangles are similar. -- All squares are similar. -- All pentagons are similar. -- All hexagons are similar. . . . etc. Any regular polygon is similar to all other regular polygons with the same number of sides.
No it does not tessellate you have to pentagons in order for it to tessellate. * * * * * It is not at all clear what "have to pentagons" has to do with this. No polygon with 7 or more sides will tessellate. Octagons will tessellate if mixed with squares but that is not "proper" tessellation since it involved more than one shape.
There are 64 sides in eight octagons.
Two regular octagons are always similar because they have equal angles and all sides are congruent. This means that they have the same shape, just different sizes.
There are regular octagons, and irregular octagons.
All eight sided polygons are known as "octagons". Octagons that have all side lengths the same are known as "regular octagons".
regular ones do but not irregular
All regular octagons have the same number of lines of symmetry, but octagons with unequal sides would have fewer lines of symmetry.
Assuming regular octagons, squares.
They can be. A regular octagon has all sides of equal length.
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They may have no lines of symmetry or they may have some - it all depends upon the shape of the irregular octagon. Only regular octagons have 8 lines of symmetry.
Strictly speaking, no, because a semi-regular tessellation must be based on regular polygons and rhombi are not regular polygons. However, octagons and rhombi can be used to make a non-regular tessellation.
No, not if it is a randomly-drawn 8-vertex shape. Octagons only have all- obtuse angles if it is a regular octagon, like the shape of a stop sign.
Squares.