Opposite angles/sides are equal.
The simple answer is no, not all parallelograms have at least one right angle. However, there are some that do. Rectangles and squares are 'special' parallelograms that all have at least one right angle.
Diagonals are congruent
The transitive property is if angle A is congruent to angle B and angle B is congruent to angle C, then angle A is congruent to angle C.
Most do, but a square or rectangle is a special case and has all right angles.
The Symmetric Property of Congruence: If angle A is congruent to angle B, then angle B is congruent to angle A. If X is congruent to Y then Y is congruent to X.
The simple answer is no, not all parallelograms have at least one right angle. However, there are some that do. Rectangles and squares are 'special' parallelograms that all have at least one right angle.
Yes. All rectangles are also parallelograms, but not all parallelograms are rectangles.
A right angle.
360
Rectangles are parallelograms with right angles.
If a parallelogram has a right angle it is a rectangle.
Diagonals are congruent
The questions doesn't make sense. An angle isn't a parallelogram. Parallelograms are types of shapes while an angle are to rays.
Many. If there is no right angle it's not a rectangle...
usually its for marking a right angle
They are quadrilaterals; opposite sides are parallel.
No, not all diagonals are perpendicular in all parallelograms. In general parallelograms, the diagonals bisect each other but are not necessarily perpendicular. However, in specific types of parallelograms, such as rhombuses, the diagonals are indeed perpendicular. Thus, the property of perpendicular diagonals is not a characteristic of all parallelograms.