Proving Figures are Parallelograms

1
CHAPTER FIVEPOLYGONS

• Section 5-6
• Proving Figures are Parallelograms

2
Theorem 10

• If a quadrilateral has on pair of opposite sides
  that are both parallel and equal, then the
  quadrilateral is a parallelogram.

3
Theorem 11

• If a quadrilateral has both pairs of opposite
  angles equal, then the quadrilateral is a
  parallelogram.

4
Theorem 12

• If a quadrilateral has diagonals that bisect each
  other, then the quadrilateral is a parallelogram.

5
Ways to show that a quadrilateralis a
parallelogram

• Show that both pairs of opposite sides are
  parallel.
• Show that one pair of opposite sides are parallel
  and equal.
• Show that both pairs of opposite sides are equal.
• Show that the diagonals bisect each other.

6
Examples Turn to page 216
7
HOMEWORK
PAGE 216 (WRITTEN EXERCISES) 1-5