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Section 8 – 2. Use Properties of Parallelograms . Vocabulary. Parallelogram: A quadrilateral with BOTH pairs of opposite sides parallel . . Theorem 8.3. If a quadrilateral is a parallelogram, then its opposite SIDES are congruent . If PQRS is a parallelogram, then and .
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Section 8 – 2 Use Properties of Parallelograms
Vocabulary Parallelogram: A quadrilateral with BOTHpairs of opposite sides parallel.
Theorem 8.3 If a quadrilateral is a parallelogram, then its opposite SIDES are congruent. If PQRS is a parallelogram, then and
Theorem 8.4 If a quadrilateral is a parallelogram, then its opposite ANGLES are congruent. If PQRS is a parallelogram, then and
Theorem 8.5 If a quadrilateral is a parallelogram, then its consecutive angles are SUPPLEMENTARY. If PQRS is a parallelogram, then
Theorem 8.6 If a quadrilateral is a parallelogram, then its diagonals bisect each other. If PQRS is a parallelogram, then
Example #1 Find the value of each variable. Theorem 8.4 ∠s are ≅ d – 21 = 105◦ +21 __+21 d = 126◦ Theorem 8.3 sides are ≅ z – 8 = 20 +8 __+8 z = 28
Example #2 Find the measure of . Theorem 8.5 are supplementary 51◦ + = 180◦ -51 _______-51 = 129◦
Example #3 Find the value of each variable in the parallelogram. Theorem 8.6 diagonals bisect each other. b – 1 = 9 a = 3
Homework Section 8-2 Page 518 – 521 3 – 11, 13 – 15, 18 – 28 even, 29, 49 - 52