64.1k views
5 votes
How many non-congruent triangles can be formed by connecting 3 of the vertices of the cube?

User Mdoar
by
4.8k points

2 Answers

7 votes

Answer:

Answer is 3, i had it for homework

Explanation:

User Aaron Reba
by
3.9k points
5 votes

Answer:

The number of non-congruent triangles that can be formed by connecting 3 of the vertices of the cube is 3 non-congruent triangles

Explanation:

From the three dimensional shape of a cube, triangles can be constructed from;

1) 6 side faces

2) 4 front face to opposite vertices triangles

3) 4 rear face to opposite vertices triangles

Each face can produce ₄C₃ = 4 triangles

Therefore;

The total number of triangles that can be formed = 4 × 6 + 4 × 4 + 4 × 4 = 56 triangles

Of the 56 triangles, it will be found that all 24 triangles from the different 6 direct faces will have the same dimension of 1, 1, √2 are congruent

The 24 triangles formed by the sides of the faces and an adjacent diagonal have the same dimension of 1, √2, √3 and are congruent

The 8 triangles formed by joining the three diagonals have the same dimension of √2, √2, √2 are congruent

Therefore, the 56 triangles comprises of a combination of three non-congruent triangle.

There are only 3 observed non congruent triangles formed by connecting three of the vertices of the cube.

User Calin Vlasin
by
4.7k points