80 likes | 220 Views
Informal Geometry. January 18, 2012. Section 6.2 – Properties of Parallelograms. Parallelogram Theorem #1 If a quadrilateral is a parallelogram, then its opposite sides are congruent. Section 6.2 – Properties of Parallelograms. FGHJ is a parallelogram. Find JH and JF.
E N D
Informal Geometry January 18, 2012
Section 6.2 – Properties of Parallelograms • Parallelogram • Theorem #1 • If a quadrilateral is a parallelogram, then its opposite sides are congruent.
Section 6.2 – Properties of Parallelograms • FGHJ is a parallelogram. Find JH and JF.
Section 6.2 – Properties of Parallelograms • Theorem #3 • If a quadrilateral is a parallelogram, then its consecutive angles are supplementary. • Uses Same-Side Interior Angles!
Section 6.2 – Properties of Parallelograms • Theorem #2 • If a quadrilateral is a parallelogram, then its opposite angles are congruent. • Uses a theorem we learned before: • If two angles are supplementary to the same angle, then they are congruent.
Section 6.2 – Properties of Parallelograms • Find the missing angle measures.
Section 6.2 – Properties of Parallelograms • With a Partner... (one writes, another speaks) • Find the missing angle measures.
Assignment • Section 6.2a • Pages 313-315 • 2-3, 22-27, 31-32, 44-46, 52-55