a square
A rectangle.
The answer depends on whether the shape is 2-dimensional or 3-d. For a 2-dimensional polygon with n sides, the minimum number is n-3 diagonals.
A triangle. Also, any shape that has no corners, such as a circle or an ellipse.
A Rectangle.
a square
a pentagon
A rectangle (or square), isosceles trapezium and some kites.
A rectangle.
There are very many attributes. Some of these are:It is a two-dimensional shape. It has four sides. The sides are of equal length. It has two pairs of parallel sides. It has four vertices. Each vertex is a right angle. It has two diagonals. The diagonals bisect each other. The diagonals meet at right angles. It has rotational symmetry of order four. It has four axes of reflective symmetry. If the sides are of rational length then the diagonals are of irrational length (and conversely).
The statements:It is a quadrilateral (a shape with 4 sides)It has two pairs of opposite sides equal of equal length which are parallelAll angles are equal at 90°The diagonals are equal in length and bisectall squares are rectangles but not all rectangles are squaresare all true about squares and rectangles
The shape you are describing is a rhombus. A rhombus has two pairs of parallel sides, with opposite sides being equal in length. The diagonals of a rhombus are also equal in length, but they do not intersect at 90 degrees; instead, they intersect at a 90-degree angle.
The answer depends on whether the shape is 2-dimensional or 3-d. For a 2-dimensional polygon with n sides, the minimum number is n-3 diagonals.
triangle
A square and a rectangle have diagonals of equal lengths
A triangle. Also, any shape that has no corners, such as a circle or an ellipse.
It is a two-dimensional (plane) shape bounded by four straight sides with equal length but which does not have an interior angle of 90 degrees. Other properties, like parallel sides, equal opposite angles, bisecting diagonals etc all follow from these.