1. Austins Guide to Geometry Lines Angles Triangles Quadrilateral Circles Other Polygons

2. Point A point is a dot in and angle. 3. Plane A plane is a sector in a space 4. Line A line a a straight line that never ends. 5. Line Segment A line segment is when any line and 2 points can be measured 6. Ray 1 point and a line that goes on forever. 7. Intersecting 2 lines that intersect 8. Perpendicular They intersect at a ninety degree angle 9. Parallel 2 lines that never meet each other. 10. Skew Lines that aren't in the same pane. 11. Acute An angle that is smaller than 90 degrees 12. Obtuse An angle thats more than 90 degrees. 13. Right An angle that is 90 degrees exact. 14. Straight 80 degrees 15. Vertex A dot in any angle 16. Vertices The point were 2 angles meet. 17. Complementary Lines across from each other like a vertical 18. Supplementary An angle that does not meet. 19. Vertical pointing up in a line that forms an angle of 90 with a flat surface 20. Opposite Vertical A B 21. Adjacent 2 angles that share a line 22. Right One angle that is 90 degrees 23. Obtuse One of that angles is more than 90 degrees 24. Acute One angle has to be 90 degrees 25. Scalene A triangle with no equal sides 26. Isosceles A triangle with 2 equal sides 27. Equilateral A triangle that has equal sides 28. Sum of internal angles The sum of all angles adding up to 180 degrees 29. Perimeter The perimeter is the addition of all the outside sides together 30. Area of a triangle The area is the length x width, squared 31. Quadrilateral A shape with 4 connected sides 32. Trapezoid A quadrilateralwith 2 parallel sides 33. Parallelogram A shape with all opposite sides being parallel 34. Rectangle A quadrilateral with four 90 degree angles 35. Rhombus A square with no right angles 36. Square A figure with 4 right angles 37. Area of a rectangle You have to multiply length x width 38. Area of a square Same thing length x width 39. Area of a parallelogramDo base x height 40. Area of a trapezoid The average of two lengths x height 41. Perimeter of a rectangle You have to add up the angles 42. Perimeter of a square To get perimeter you add up all the angles 43. Chord Segment connecting 2 points 44. Diameter A line segment that passes through the center of a circle 45. Radius A line segment with one end point 46. Sector

• A region enclosedby to radii and the arc joiningtheir endpoints

47. Circumference The distance around the circle 48. Area of a circle The space inside 49. Hexagon A shape with 6 sides 50. Octagon A shape that has 8 sides 51. Regular polygon All sides are congruent 52. Perimeter of a square To get perimeter you add up all the angles