IV. Classes 4-5

A. Participants engage in Triangle Investigations.

Participants should choose investigations that involve:

• Classifying triangles according to their properties (e.g. acute, obtuse, right, isosceles, equilateral, equiangular, scalene)
• Solving problems involving the area and perimeter of triangles
• Making graphical representations of triangles and shapes composed of triangles
• Using Pythogorean Theorem, right triangle rules (30-60-90, 45-45-90) and ratios for sine, cosine and tangent of angles to solve problems

1) Week 4: Choose from recommended investigations concerned with classifying and investigating a variety of triangles

• Constructing Quadrilaterals 1
• In or Out?
• Classified Information
• Rationalize This
• Balancing the Triangular Totter
• Shark Attack!

2) Week 5: Choose from investigations focused on area, perimeter, and trigonometry with triangles

• All Swimmed Out
• Trigonometric Ratios
• Interactive Pythagoras
• Trigonometric Ratios
• To Be or Not to Be
• Lining Up to Find Triangles
• Same Area: Triangle and Square
• Biggie Size It
• Transforming Triangle
• Casting Shadows
• Capture the Flag

B. Participants add write-ups to their online portfolios
C. Introduction of the spreadsheet program

Triangle investigations using the spreadsheet program:

• Rationalize This
• Tri-Square Trios
• Sum of Angles in a Polygon
• Optimal Quadrilaterals

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Additional Resources for Weeks 4-5

• Dictionary Terms with Comprehensive Activities
  • Acute Triangle
  • Altitude of a Triangle
  • Centroid
  • Circumcenter
  • Congruent Triangles
  • Equiangular Triangle
  • Equilateral Triangle
  • Hypotenuse
  • Isosceles Triangle
  • Leg of a Triangle
  • Median of a Triangle
  • Obtuse Triangle
  • Orthocenter
  • Pythagorean Theorem
  • Pythagorean Triple
  • Right Triangle
  • Scalene Triangle
  • Tangent
  • Tangent Line
  • Triangle Inequality
• External Resources
  • Pythagorean Theorem
  • Special Right Triangles: 45-45-90
  • Trigonometry: The 30-60-90 Triangle

Return to the Geometry Syllabus.