A rectangle or a square.
If it has at least one set of parallel sides, then at least one set of angles are congruent
a paralelagram
the shape? no, not always. but they are always at least similar figures. but the angles alone are always congruent
Yes. The two base angles (the angles opposite the equal sides) are always congruent.
A rectangle.
at least one pair of opposite sides is parallel
Adjacent angles of a square? You have to have at least two squares to compare the congruency of angles. Since all the angles of a square equal 90 degrees, adjacent angles of any TWO squares will be congruent. I suggest you look up the definition of CONGRUENT. - wjs1632 -
No. Except for the case of a square (a special case of rhombus), a rhombus will have 2 congruent acute angles, and 2 congruent obtuse angles. The square has 4 right angles. In fact, every quadrilateral will have either all 4 angles equal to right angle (square and rectangle), or will have at least 1 obtuse angle (also at least 1 acute).
Any quadrilateral in which at least one (and therefore at least two) angles are not right angles is not a rectangle. The majority of these do not have a specific name.
No.
No. The only requirement for a triangle to be a 45-45-90 triangle is for it to have at least two congruent sides/angles. The measure of the two congruent angles can be anything.
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.