Question

How many equilateral triangles in the plane have two vertices in the set {(0, 0), (0, 1), (1, 0), (1, 1)}?

Answer 1

Answer:

12

Step-by-step explanation:

There are 4 points, so there are C(4,2) = 4C2 = 6 pairs of  

points and since two equilateral triangles can be drawn having

that pair of points as vertices, there are 12 equilateral  

triangles that can be drawn having two vertices in the set  

{(0,0), (0,1), (1,0), (1,1)}.