Many shapes. If it is a triangle, it is an isosceles triangle. A quadrilateral (4 sides) may be several types depending on other conditions. Just a quadrilateral (adjacent sides congruent and no other special condition) a parallelogram, a rhombus, a square, and a rectangle (all are quadrilaterals). But there is nothing that says a pentagon, hexagon, etc. cannot have t congruent sides.
parrlelagram
I think a trapezoid.
Yes, all trapezoids must have one pair of congruent sides.
No. Most trapezoids don't even have one pair of congruent sides. Only isosceles trapeoids have one pair; none have more than one pair.
It could be any irregular polygon other than a triangle.
parrlelagram
trapezoid
By definition, a trapezoid only must have exactly one pair of parallel sides. An isosceles trapezoid does have one pair of congruent sides, but not all trapezoids will have exactly one pair of congruent sides.
I think a trapezoid.
Yes, all trapezoids must have one pair of congruent sides.
This quadrilateral is a trapezoid. In a trapezoid, one pair of opposite sides is parallel, and one pair of opposite sides is congruent. The other two sides are not parallel or congruent.
Yes, an isosceles trapezoid has one pair of congruent opposite sides and congruent base angles
A four-sided shape is a quadrilateral. With only one pair of parallel sides, it would be called a trapezoid (UK trapezium).
No. By definition, a rectangle must have TWO pairs of parallel sides. Also, each pair of parallel sides will be congruent. *If this is not happening with your shape, it isn't a rectangle.
No. Most trapezoids don't even have one pair of congruent sides. Only isosceles trapeoids have one pair; none have more than one pair.
No, a parallellogram is a quadrilateral with two pair of congruent sides and a trapezoid is a quadrilateral with only one pair of congruent sides.
It could be any irregular polygon other than a triangle.