1. Sections 1.5 & 1.6

2. Warm up (Left side)

4. Definitions: Angles Classified by measure : An acute angle has a measure between 0 o and 90 o A right angle has a measure of exactly 90 o An obtuse angle has a measure between 90 o and 180 o A straight angle has a measure of 180 o

5. Definition: Congruent Angles Two angle are congruent angles if they have the same measure. **To show that two angles in a diagram are congruent, we put a matching arc inside each angle. ***We use “m” to say “measure of…”

6. Definition: Angle Bisector : An angle bisector is a ray that divides an angle into two congruent angles. <XYW ≅ <ZYW or m<XYW=m<ZYW

7. Complementary and Supplementary Angles Complementary Angles: the sum of their measures is 90 o. Supplementary Angles : the sum of their measures is 180 o. Adjacent angles Two angles that share a common vertex and side, but have no common interior points.

8. Linear Pair: Linear Pair is 2 adjacent angles whose sides form a straight line. **linear pair are always supplementary. Vertical Angle Pairs: Vertical angles are formed when two lines intersect. The angle pairs only touch at the vertex. ***Two pairs of vertical angles are formed when two lines intersect.

10. A Polygon is a closed two-dimensional shape with straight (not curved) sides. A polygon is convex if no line that contains a side of the polygon contains a point in the interior of the polygon. A polygon that is not convex is called concave.

11. Equilateral polygon - all sides are congruent. Equiangular polygon - all interior angles are congruent. Regular polygon - a convex polygon that is both equilateral and equiangular.

12. Polygon Names 3 sidesTriangle 4 sidesQuadrilateral 5 sidesPentagon 6 sidesHexagon 7 sidesHeptagon 8 sidesOctagon 9 sidesNonagon 10 sidesDecagon 11 sidesUndecagon 12 sidesDodecagon n sidesn-gon