The adjacent angles paralellogram are congruent. Always, sometimes, or never
The adjacent angles of a parallelogram are supplementary
The adjacent angles of a parallelogram are complementary, that is, they add up to 180°.
If they are 90° each, then your parallelogram becomes a rectangle, so the correct choice would be
"sometimes"
The statement "The adjacent angles of a parallelogram are congruent" is true, and it holds for all parallelograms. Therefore, the correct answer is "Always."
To understand why this statement is always true, we can consider the properties of a parallelogram. A parallelogram is a quadrilateral with opposite sides that are parallel and congruent. It also has opposite angles that are congruent.
When we examine the adjacent angles of a parallelogram, we notice that they are formed by intersecting sides. Since parallel lines cut by a transversal create equal corresponding angles, the adjacent angles in a parallelogram are congruent.
In summary, the adjacent angles of a parallelogram are always congruent because of the properties of parallel lines and transversals.