2. 1. Definitions 2. Segments and Lines 3. Triangles 4. Polygons and Circles 5. 2D Perimeter/Area and 3D Volume/Surface Area

3. Lines extends indefinitely Segments are portions of lines that starts at a point and end at another points. These are called Endpoints Rays starts at a point and extends indefinitely in one direction Things that are “Congruent” are equaled in measurement Angles are the space in-between two connected rays that is usually measured in Degrees Vertical Angles are two opposite angles formed by two intersecting lines. Vertical angles are also congruent Complementary Angles are two angles whose sum is 90 0 Supplementary Angles are two angles whose sum is 180 0 A Linear Pair are pairs of connected angles that form a straight line and are also supplementary angles

6. Slopes in Geometry is the same as in Algebra Parallel lines have the same slope a b c d e f g h i j k l m n o p

7. Triangle Sum Theorem: The sum of all the angles within a triangle is equal to 180 0 Types of Triangles by Sides Equilateral – All sides of a triangle have the same length Isosceles – Exactly two sides of a triangle have the same length Scalene – All sides of the triangle have different length Types of Triangles by Angle Acute – All angles in the triangle have a measure of less than 90 0 Obtuse – Exactly one angle in a triangle has a measure of more than 90 0 Right – Exactly one angle in a triangle has a measure of 90 0

9. Special Right Triangles 45-45-90 30-60-90

10. Two Triangles are congruent if they satisfy the conditions in one of the following: SSS, SAS, AAS, ASA, Leg-Hypotenuse Two Triangle are similar if all the ratios between corresponding parts of the triangles are the same

11. Polygons are shapes with 3 or more straight sides and angles Interior Angle Sum on a polygon is defined by 180(n-2) Where n is the number of sides A couple of Polygons includes Triangle, Quadrilaterals, Pentagon, Hexagon, Heptagon, Octagon, Nonagon, and Decagon Examples of Quadrilaterals include Parallelograms, Rhombus, Rectangle, Square, Kite Keep in mind that all regular polygons can be broken up into triangles

12. Circles are perfectly round shapes Diameter is any line drawn from one end of a circle to the other end that must pass through the center Radius is the any line drawn from the center to one end of a circle Chords are any line drawn from one end of a circle to another end that doesn’t pass through the center Circumference of a circle is the distance around the circle defined as C = 2πr Arc length is a portion of the circumference

13. Perimeter is the distance around a shape In particular for a quadrilateral, the formula is 2l + 2w Area is the flat space a shape can hold Volume is the space a solid can hold Surface area is the sum of all the areas of a solid Solids include Prisms, Cylinders, Pyramids and Spheres All formulas for area, volume, and surface area are on the first page of each section