1. Warm up 1. What is the name of this shape? Find the area and perimeter. Rectangle A = 31.5 sq cm P = 27 cm 3 cm 10.5 cm 2. This shape is a rhombus. Its perimeter is 80 units. What is the length of each side? 20 units 2x + 3x + 7 3. Find the length of each of the given sides then find the perimeter & area. x = 4 Each side = 11 inches 4. Find the perimeter and area. 3 3 3 3 5 7 A = 107 sq units P = 48 units P = 50 in. A = 112 in 2 18 inches 10 inches 8 in.

2. Vocabulary Complementary angles – TWO angles whose measures have a sum of 90° Supplementary angles – TWO angles whose measures have a sum of 180° Vertical angles – when 2 lines (or segments) intersect, 4 angles are formed. The pair that are across the vertex from each other are called vertical angles AND they are congruent. A B 30° 60° C D 80° 100° EF  E =  F ~

3. Geometry Notation (secret geometry code) Geometric item Looks like LabeledNotation Point..A.A A or point A Line l A B C line l AB or AC or BC or BA or CA or CB Plane L M N Z plane LMN or R R

4. More notation Geometric item Looks like LabeledNotation line segment ______ AB or BA angle  1  A  XYZ or  ZYX Vertex MUST be in the middle A B A X Z Y 1

5. Linear Pair A pair of angles that make a line AB m  A + m  B = 180° 152°B 180 – 152 = m  B 28 = m  B 3x - 4 x 3x – 4 + x = 180 4x – 4 = 180 4x = 184 X = 46 134° 46°

6. Find the measures of all the angles Vertical Angles/Linear pair combo 2x - 4 x 2x – 4 + x = 180 X = 61.333 61.3° 118.6°

7. Just for fun… How would you set this one up? 4x - 5 3x + 2 4x – 5 = 3x + 2 Solve and find the measure of each angle X = 7 Each angle = 23°

8. Transversal When 2 lines are intersected by another line, that ‘other line’ is called a TRANSVERSAL. Let’s look at this closer… How many angles are there? none Now, how many angles are there? 8 These 8 angles are a pretty big deal to us!!!

9. interior INTERIOR –The space INSIDE the 2 lines EXTERIOR -The space OUTSIDE the 2 lines exterior

10. Special Angle Pairs Interior Angles <3 & <6 are Alternate Interior angles <4 & <5 are Alternate Interior angles <3 & <5 are Same Side Interior angles <4 & <6 are Same Side Interior angles 1 4 2 6 5 78 3 Exterior Angles <1 & <8 are Alternate Exterior angles <2 & <7 are Alternate Exterior angles <1 & <7 are Same Side Exterior angles <2 & <8 are Same Side Exterior angles

11. Special Angle Relationships WHEN THE LINES ARE PARALLEL ♥Alternate Interior Angles are CONGRUENT ♥Alternate Exterior Angles are CONGRUENT ♥Same Side Interior Angles are SUPPLEMENTARY ♥Same Side Exterior Angles are SUPPLEMENTARY 1 4 2 6 5 78 3 If the lines are not parallel, congruency DOES NOT EXIST.

12. Assignment Pg 77; 8 - 11 Back to 2.1.2 & 2.1.3 powerpoint

13. Let’s Practice m<1=120° Find all the remaining angle measures. 1 4 2 6 5 78 3 60° 120°