Two.
It can be but a square and a rhombus diagonals are also perpendicular and therefore intersect at 90 degrees and they too are both quadrilaterals.
Yes
A quadrilateral that does not always have congruent diagonals is a trapezoid. In a trapezoid, which has at least one pair of parallel sides, the diagonals are generally not congruent unless it is an isosceles trapezoid. Other types of trapezoids can have diagonals of different lengths. Thus, congruent diagonals are not a defining characteristic of all trapezoids.
Every closed figure with at least 4 sides has at least 2 diagonals. Every quadrilateral (figure with exactly 4 sides) has exactly 2 diagonals. That includes all parallelograms, rhombera, rectangles, squares, trapezoids, diamonds, and kites, as well as all other irregular quadrilaterals.
No, the diagonals of a trapezoid are not always congruent. A trapezoid is a quadrilateral with at least one pair of parallel sides. The diagonals of a trapezoid connect the non-parallel vertices, and their lengths can vary depending on the specific dimensions of the trapezoid. In a trapezoid where the non-parallel sides are of equal length, the diagonals will be congruent, but this is not always the case.
No. Even in the non-US use of the term (a quadrilateral with at least one set of parallel lines), the lengths of the parallel lines may not be the same, and/or the angles formed by each adjacent side may be different (as in a rhomboid), resulting in diagonals of extremely different lengths.Only in rectangles are diagonals "always" of equal length.
There is no such thing as a least common number.
You need at least two things to find something in common between them.
least common multiple
1 is the least common factor of the number 2, number 4 and number 7. 28 is the least common multiple of the number 2, number 4 and 7.
the least common multiple, or LCM
least common multiple, or LCM.