I introduce and work through 6 examples of problems involving 30 60 90 triangles and 45 45 90 triangles. All work is done in exact form and not rounded off decimals from a calculator.
EXAMPLES at 3:30 4:47 10:05 11:46 14:05 19:03

Check out www.ProfRobBob.com, there you will find my lessons organized by class/subject and then by topics within each class.

1. Points Lines & Planes in Geometry
2. More Postulates & Theorems Points, Lines, & Planes
3. Segment, Ray, Distance on a Number Line
4. Introduction to Angles
5. Special Angle Pairs
6. Basic Constructions Segment & Angle
7. Angle and Segment Bisector Constructions
8. Distance Formula & Pythagorean Theorem
9. Midpoint Formula
10. Perimeter of a Plane Region
11. Area of a Plane Region
12. Deductive Reasoning If Then Statements
13. Intro to 2 Column Geometry Proofs
14. Congruent Angles
15. Parallel Lines & Skew Lines, Angles formed by a Transversal
16. Parallel Lines & Transversal Angles
17. Proving Lines Parallel
18. Parallel & Perpendicular Lines Proof
19. Angles of Triangles and Parallel Lines
20. Graphing Lines in Slope-Intercept form y=mx+b
21. Equations of Lines and Graphing
22. Rate of Change Slope & Point Slope Equation of Lines
23. Equations of Parallel and Perpendicular Lines
24. Congruent Polygons & Third Angle Theorem
25. Congruent Triangles SSS SAS
26. Congruent Triangles ASA AAS
27. Non Congruence Theorems AAA SSA
28. CPCTC Corresponding Parts of Congruent Triangles are Congruent
29. Isosceles & Equilateral Triangle Properties
30. Equilateral Triangle / Equiangular Triangle
31. Congruent Right Triangles HL Hypotenuse Leg Theorem
32. Triangle Midsegment Theorem
33. Proving Midsegment Theorem
34. Perpendicular Bisector Theorem
35. Angle Bisector Theorem
36. Triangle Perpendicular Bisectors & Circumcenter
37. Triangle Angle Bisectors & Incenter
38. Medians of Triangles & Centroid
39. Altitudes of Triangles and Orthocenter
40. Triangle Inequality Theorem
41. Hinge Theorem Inequalities 2 Triangles
42. Polygon Angle Sum Theorems
43. Properties of Parallelograms
44. Proving Quadrilaterals are Parallelograms
45. Rhombuses, Rectangles, and Squares
46. More Examples Rhombus & Rectangle
47. Properties of Trapezoids & Mid Segment Theorem
48. Properties of Kites
49. Polygons in Coordinate Plane
50. Ratios & Proportions
51. Proportions and Similar Polygons / Similar Figures
52. Proving Triangles are Similar AA SAS SSS
53. Similarity in Right Triangles
54. Side Splitter Theorem Proportions in Triangles
55. Proportions in Triangles Angle Bisector
56. Pythagorean Theorem
57. Converse Pythagorean Theorem & Triples
58. Special Right Triangles 45-45-90 30-60-90
59. Right Triangle Trigonometry Part 1: Finding Missing Sides
60. Right Triangle Trigonometry Part 2: Solving for Acute Angles
61. Angle of Elevation and Depression Right Triangle Trig
62. Area Parallelograms and Triangles
63. Area Trapezoid Rhombus Kite
64. Area of Regular Polygon Introduction with Hexagon Examples
65. Area Regular Polygons with Trigonometry
66. Perimeter and Area Ratios of Similar Figures
67. Circle Intro and Arc Length
68. Sector and Segment Area in Circles
69. Segment Area in Circles Quicker Methods
70. Geometric Probabilities Length
71. Geometric Probabilities Area
72. Surface Area of a Right Prism
73. Surface Area Of a Cylinder
74. Surface Area of a Regular Pyramid Non-Trig Examples
75. Surface Area of a Pyramid with Trigonometry
76. Surface Area of a Cone
77. Volume of a Prism & Volume of a Cylinder
78. Volume of a Pyramid 3 Examples
79. Volume of a Cone 3 Examples
80. Surface Area of a Sphere & Volume of a Sphere
81. Tangent Lines to Circles
82. Given a Tangent Line & Circle Find the Point of Tangency
83. Chords Arcs and Diameters in Circle
84. Inscribed Angles in Circles and Tangent Lines
85. Angles in Circles Chords Secants Tangents and Arcs
86. Segment Lengths in Circles with Chords, Secants, and Tangents

In this series, the very helpful and fun math teacher Mr. Tarrou teaches students an entire course on geometry from start to finish. His videos are friendly, easy to understand, entertaining, and very well organized, all thanks to Mr. Tarrou great dedication to teaching and mathusiasm