Triangle Classifications
You have learned 3 ways to classify triangles by their side engths and 3 ways to classify them by their angle measures.
We usually classify triangles by choosing one term from each column and there are nine possible combinations. However, not all combinations are possible. For each side classification, show examples of which angle classifications can be combined with that side classification.
| By Sides | By Angles |
| Scalene | Acute |
Isosceles | Obtuse |
Equilateral | Right |
- NOTE Isosceles, Equilateral and Right triangles should be constructed so that they pass the drag test. Scalene, acute and obtuse do not need to pass the drag test, but should clearly show those characteristics.
- Use a textbox to label each example with its side and angle classification or use a textbox to explain why certain combinations can’t be made.
- Measure angles and side lengths to clearly show that each triangle has the characteristics of the classification.
Scalene Triangles
In the box below show if the following triangles are possible: Acute Scalene, Obtuse Scalene and Right Scalene.
- Measure angels and side lengths to clearly show that each triangle has the characteristics of the classification or explain in a textbook why certain combinations cannot be made
- Right Scalene Triangle Must Pass the Drag Test
In the box below show if the following triangles are possible: Acute Isosceles, Obtuse Isosceles and Right Isosceles.
- Measure angels and side lengths to clearly show that each triangle has the characteristics of the classification or explain in a textbook why certain combinations cannot be made
- All Isosceles Triangles Must Pass the Drag Test
In the box below show if the following triangles are possible: Acute Equilateral, Obtuse Equilateral and Right Equilateral.
- Measure angels and side lengths to clearly show that each triangle has the characteristics of the classification or explain in a textbook why certain combinations cannot be made
- All Equilateral Triangles Must Pass the Drag Test
Explore which of the following triangles can be made. Explain what you discover in a textbox. (Right Triangles, Isosceles Triangles and Equilateral Triangles must pass the drag test.)
- Isosceles and Equilateral
- Acute and Right
- Scalene and Isosceles
- Acute and Obtuse