1. Today…. Go over homework from 5-1
Do practice worksheet for 5-1 (collected and graded)
Notes for 5-2
Assign Homework

2. Here we go!! Let’s put the answers on the board!!
Let’s do the worksheet!

3. Section 5.2 Ways to Prove that Quadrilaterals Are Parallelograms
Let’s go backwards with the 5 ways to prove a quadrilateral is a parallelogram!!!

4. Recap (quietly write down your answers):
What is a quadrilateral?
(a 4-sided figure)
What is a parallelogram?
(both pairs of opposite sides parallel)
Is every quadrilateral a parallelogram? no
Is every parallelogram a quadrilateral?
yes

5. Prove a Quadrilateral is a Parallelogram!
Objective
Prove a Quadrilateral is a Parallelogram!

6. Yesterday…(don’t write)
Opposite sides of a parallelogram are__________.
CONGRUENT!!

7. Converse (don’t write):
If AB CD and
BC DA, then ABCD is a
||-ogram.
If both pairs of opposite sides of a quadrilateral are congruent, then the quadrilateral is a parallelogram. C B D A

8. Yesterday…(don’t write)
Opposite angles of a parallelogram are __________
CONGRUENT!!

9. Converse (don’t write):
If <A <C and
<B <D, then ABCD is a ||-ogram.
If both pairs of opposite angles of a quadrilateral are congruent, then the quadrilateral is a parallelogram. B C D A

10. Yesterday…(don’t write)
Diagonals of a parallelogram ________ each other.
BISECT!!

11. Converse (don’t write):
If AB DC and
BC AD, then ABCD
is a ||-ogram.
If the diagonals of a quadrilateral bisect each other, then the quadrilateral is a parallelogram. B C D A

12. Theorem 5-5 (write!!!):
If BC AD and
BC || AD, then ABCD
is a ||-ogram.
If one pair of opposite sides are parallel and congruent, then the quadrilateral is a parallelogram. B C D A

13. The Big 5!! (write)!
Def of parallelogram: Both pairs of opposite sides are parallel.
Theorem 5-4: Both pairs of opposite sides are congruent.
Theorem 5-5:One pair of opposite sides are both congruent and parallel.
Theorem 5-6: Both pairs of opposite angles are congruent.
Theorem 5-7:Diagonals bisect each other.

14. Go to page 173 and do Write yes or no, and the theorem or definition that proves it so. That rhymed.
yes, thm 5-4
Yes, thm 5-5 No
Yes, thm 5-7
Yes, either def. of //gram, or thm 5-6
Yes, def of //gram

15. Closure! Name the definition or theorem on little piece of paper!
BE = ED, CE = EA
m<BAD = m<DCB, m<ADC = m<CBA
BC || AD, AB || DC
4. BC || AD, BC = AD B C E D A

16. Homework!
Worksheet
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