WARMUP mABC 14 x 2 mCBD 6 x

WARMUP - mÐABC = 14 x + 2, mÐCBD = 6 x + 1, mÐABD = 25 x – 27 C A D mÐABC = 14 x + 2 B mÐABC = 14(6) + 2 = 86 mÐABC + mÐCBD = mÐABD 14 x + 2 + 6 x + 1 = 25 x – 27 20 x + 3 = 25 x – 27 3 = 5 x – 27 30 = 5 x 6=x x=6 mÐABC = 86 mÐCBD = 6 x + 1 mÐCBD = 6(6) + 1 = 37 mÐABD = 25 x - 27 mÐABD = 25(6) - 27 = 123 mÐCBD = 37 mÐABD = 123

What are some special angle relationships? AGENDA: • WARMUP • REVIEW ANGLES FROM WEDNESDAY • SPECIAL ANGLE PAIRS • TEST FRIDAY

Complementary Angles Definition: two angles whose measures have the sum of 90. 20 70 55 35 Complementary Angles may or may not be Adjacent Angles.

Supplementary Angles Definition: two angles whose measures have the sum of 180. 110 55 70 125 Supplementary Angles may or may not be Adjacent Angles.

Linear Pair Definition: two supplementary, adjacent angles. 60 120 Linear Pair = A Pair of Angles that forms a Line.

Vertical Angles Definition: two non-adjacent angles formed by intersecting lines. 1 3 4 2 Ð 1 and Ð 2 are vertical angles. Ð 3 and Ð 4 are vertical angles.

What do you notice? 1 3 4 2 Ð 1@Ð 2 Ð 3@Ð 4 Theorem: Vertical Angles are Congruent.

Applying new concepts with Algebra… 102 10 x - 18 A C Q B 8 x + 6 102 Find x. D We know vertical angles are congruent; therefore the measure of vertical angles are equal and we can set these two expressions equal to one another. 10 x – 18 = 8 x + 6 2 x = 24 x = 12