Chapter 8 Geometry Flashcards
Polygon exterior angles theorem
Sum of exterior angles=360
Opposite sides of a parallelogram
If a quadrilateral is a parallelogram, then its opposite sides are congruent.
Opposite angles of a parallelogram
If a quadrilateral is a parallelogram, then its opposite angles are congruent.
Consecutive angles of a parallelogram
If a quadrilateral is a parallelogram, then its consecutive angles are supplementary.
Diagonals of a parallelogram
If a quadrilateral is a parallelogram, then its diagonals bisect each other.
Opposite sides of a quadrilateral (8.3)
If both pairs of opposite sides of a quadrilateral are congruent, them the quadrilateral is a parallelogram.
Opposite angles of a quadrilateral (8.3)
If both pairs of opposite angles of a quadrilateral are congruent, then the quadrilateral is a parallelogram.
Pair of opposite sides of a quadrilateral (8.3)
If one pair of opposite sides of a quadrilateral are congruent and parallel, then the quadrilateral is a parallelogram.
Diagonals of a quadrilateral (8.3)
If the diagonals of a quadrilateral bisect each other, then the quadrilaterals a parallelogram.
Angle converses(3)
Alt. ext. angle converse-proves parallel if these are congruent
Alt. int. angle converse-proves parallel if these are congruent
Corresponding angle converse-proves parallel if these are congruent
Angle theorems(3)
Alt. ext. angles theorem-proves congruency if lines are parallel
Alt. int. angles theorem-proves congruency if lines are parallel
Corresponding angles theorem-proves congruency if lines are parallel
Polygon interior angles theorem
Sum of interior angles=(n-2)180
Where n=the amount of sides
Definition of a parallelogram
If both pairs of opposite sides of a quadrilateral are parallel, then it’s a parallelogram.
