Instructional Unit: Triangles

 

Day 1 - Classifying Triangles

- Acute vs. Obtuse triangles

- Scalene, Isosceles, and Equilateral triangles

- Right triangles

*Exploration with GSP: Learning to construct triangles


Day 2 - Measuring Angles

- Angle Sum Theorem

- Exterior Angle Theorem

- Third Angle Theorem

- Remote Interior Angles

*Exploration with GSP: Measuring Angles


Day 3 and 4 - Congruent Triangles

- Definition of congruent triangles

- Properties of congruent triangles

- SSS congruency

- SAS congruency

- ASA congruency

- AAS congruency

- Isosceles Triangle Theorem

*Exploration with GSP: Measuring lengths of sides


Day 5 - Special Segments in Triangles

- The perpendicular bisector

- The median

- The altitude

- The angle bisector

*Exploration with GSP: Constructing special segments


Day 6 and 7 - Angle Inequalities

- Definition of inequality

- Exterior Angle Inequality Theorem

- Triangle Inequality Theorem

- Inequalities with 2 triangles

i) SAS Inequality Theorem

ii) SSS Inequality Theorem


Day 8 - Right Triangles

- Special congruencies

i)Legs of a Right Triangle Congruency

ii) Hypotenuse and Acute Angle Congruency Theorem

iii) Leg and Acute Angle Congruency Theorem

iv) Hypotenuse and Leg Conruency Theorem

- Special right triangles

i) 45 - 45 - 90

ii) 30 - 60 - 90

*Exploration with GSP: Constructing a right triangle


Day 9 and 10 - Special Properties of Right Triangles

- Geometric Mean

- Properties of the altitude from a right angle

- Pythagorean Theorem

*Exploration with GSP: Construct squares from sides of a right triangle to see visual of Pythagorean Theorem


 


return