Similar shapes need to have the same number of sides, the same angles and the ratio of the sides needs to be the same. Rectangles are not always similar to each other because they can have different dimensions, which would break the "same ratio" rule.
No. Two regular hexagons are always similar to each other, but two random hexagons are not necessarily similar.
Parallelogram
always
Only if 2 sides are parallel with each other, and the other two sides are also parallel with each other. All squares are rectangles. All rectangles are parallelograms. All parallelograms are 4 sided. But not all 4-sided are parallelograms, not all parallelograms are rectangles, and not all rectangles are squares.
They can b different sizes
All squares are rectangles, as they meet the definition of having four right angles and opposite sides that are equal in length. However, not all rectangles are similar to each other; similarity requires that corresponding angles are equal and corresponding side lengths are proportional. Since rectangles can have different side lengths, they are not necessarily similar unless they have the same aspect ratio. In contrast, all squares are similar to each other because they have equal sides and angles.
Yes the 4 corners of a rectangle are perpendicular to each other and its opposite sides are parallel to each other.
No. Two regular hexagons are always similar to each other, but two random hexagons are not necessarily similar.
Parallelogram
always
Rectangles must always have 4 sides. As there are two rectangles, there must be 8 sides. However, if these two rectangles have identical sized sides and they are placed against each other so that they look like one rectangle, there will only be 4 sides.
there are two reasons one is they could be different ways or they could be plastic shapes or a real thing
The diagonals of a square (which always bisect each other) are the same length.
Yes, in similar triangles, the angles are always congruent, and the sides have the same proportions to each other.
Only if 2 sides are parallel with each other, and the other two sides are also parallel with each other. All squares are rectangles. All rectangles are parallelograms. All parallelograms are 4 sided. But not all 4-sided are parallelograms, not all parallelograms are rectangles, and not all rectangles are squares.
Sometimes.
They can b different sizes