Session 2, Part A:
Different Triangles

In This Part: Drawing Triangles | Classifying Triangles

The following shows how triangles can be classified according to some of their features:

Angles:

Right Triangles

Acute Triangles

Obtuse Triangles

 One right (90°) angle All angles less than 90° One angle more than 90°

Sides:

Equilateral Triangles

Isosceles Triangles

Scalene Triangles

 All three sides are the same length.
 Two sides are the same length.
 All three sides are different lengths.

Size:

Similar Triangles

Congruent Triangles

 Same shape, possibly different size Same size and shape

Problem A5

More than one feature can be combined into a triangle. Decide which of the following combinations are possible. If the combination is possible, draw a sketch on a piece of paper. If not, explain why not.

 a. a scalene right triangle b. an isosceles right triangle c. an equilateral right triangle d. a right triangle that is also obtuse

 Session 2: Index | Notes | Solutions | Video