Yes.
The angle bisectors of a regular polygon are always concurrent. And the point that they meet at is also the meeting point of the perpendicular bisectors of the sides. If it is a polygon with an odd nmber of sides, the "medians" [line from vertex to mid-point of opposite side] and "altitudes" [perpendicular from vertex to opposite side] will also meet at the same point.
Equilateral triangles have 3 perpendicular bisectors
True, the diagonals of a rhombus are perpendicular bisectors of one another.
nope
No
Altitude: The altitude of a triangle is a perpendicular segment that connects a vertex and its opposite side. Let's construct the altitude of a triangle using a new triangle.
Yes.
The angle bisectors of a regular polygon are always concurrent. And the point that they meet at is also the meeting point of the perpendicular bisectors of the sides. If it is a polygon with an odd nmber of sides, the "medians" [line from vertex to mid-point of opposite side] and "altitudes" [perpendicular from vertex to opposite side] will also meet at the same point.
Equilateral triangles have 3 perpendicular bisectors
No, they are just bisectors. The angle between them is not (usually) the 90o required to be perpendicular.
The vertex
True, the diagonals of a rhombus are perpendicular bisectors of one another.
rectangle
nope
all three perpendicular bisectors elongate to meet at the incenter of the triangle.
If the diagonals are congruent and are perpendicular bisectors of each other then the parallelogram is a square. If the diagonals are not congruent but are perpendicular bisectors of each other then the figure would be a rhombus.