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

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

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!!!

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

Prove a Quadrilateral is a Parallelogram! Objective Prove a Quadrilateral is a Parallelogram!

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

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

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

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

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

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

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

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.

Go to page 173 and do 1-9. 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

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

Homework! Worksheet Page 174 1-5 Page 175 19-22