A parallelogram has two sets of parallel sides. It can have four sides that are equal in length. That is why a square is also a parallelogram. You can have a parallelogram with two sets of parallel sides, all of which are equal in length, but they do not meet in right angles. It looks kind of like a lopsided or squished square, and it is called a rhombus.
A triangle with two equal sides and two equal angles is called an isosceles triangle.
A square has 3 sets of parallel sides of equal length AND all the angles are 90 degrees. A rhombus has 2 sets of parallel lines of equal length, but the angles aren't all 90 degrees.
The 3 sides of an equilateral triangle are all equal in length and its 3 interior angles are equal in size each measuring 60 degrees
A Square
All three sides are congruent (equal in length); all three angles are congruent (same measure).All three sides are congruent (equal in length); all three angles are congruent (same measure).All three sides are congruent (equal in length); all three angles are congruent (same measure).All three sides are congruent (equal in length); all three angles are congruent (same measure).
A hexagon has all six sides in equal length and all angles in equal measure.
square
An equilateral triangle.
regular
isosceles triangle has two sides equal in length and two angles of the same measure;
The word regular, for polygons, refers to all sides equal length, and all angles equal measure. A scalene triangle by definition, has not two sides equal, and all of the angles are different measure.
A rhombus has four sides of the same length, and a rectangle has four angles of the same measure. A square has equal sides and equal angles.
regular polygonA square
You prove that the two sides (not the bases) are equal in length. Or that the base angles are equal measure.
No. They must have at least three sides of equal length, and all angles must be of equal measure.
A polygon with sides of equal length and equal angles is termed a regular polygon.