A right triangle.
Any shape, other than a triangle can have a pair of perpendicular sides.
The first geometric shape that comes to mind with no perpendicular sides is a triangle.
A`isoseles duhhh
A triangle has no parallel sides but a right angle triangle has perpendicular sides that meet at 90 degrees.
Perpendicular means meeting at a right angle. A right triangle has 2 sides that are perpendicular, so it has 1 pair of sides that are perpendicular They are known as the "legs" of the right triangle.
It could be a right angle triangle
It fits the description of a right angle triangle
I am sure there are several; the simplest would be a right triangle, which means, a triangle with a right angle.
The question contradicts itself. A dodecagon need not have any perpendicular sides.
shape no pairs of perpendicular sides
Any polygon can have only 1 pair of perpendicular sides.
Yes. The orthocenter is the intersection of the altitudes; the circumcenter is the intersection of the perpendicular bisectors of the three sides of the triangle. The perpendicular bisector of and altitude to a given side are parallel, so they can coincide at the common center only if they are the same; that means that the opposite vertex is on the perpendicular bisector, so the other two sides are equal. Thus each pair of sides are equal, so the triangle is equilateral.