three
no
Not sure about vertices's. The circumcentre is equidistant from a triangle's vertices (no apostrophe).
Of course. The vertices of a triangle, and any three vertices of any other polygon, are non-collinear. In the case of a triangle and a quadrilateral, if you had three collinear vertices, then you couldn't have the polygon.
The vertices of a triangle are the endpoints. In other words, when the sides of the triangle intersect, they form a vertex of a triangle. A triangle has a total of three vertices.
Vertex of a triangle is any of its 3 corners and the plural of vertex is vertices
Vertices are the main property of triangles. No vertices, no triangle.
A triangle has 3 vertices.
Any two vertices of a triangle are connected by a side.
They are the points where pairs of sides come together, just as they are in any triangle.
A triangle has 3 vertices and 3 sides
They are the 3 corners of the triangle and vertices is the plural of vertex
No. and it is not vertices's! vertices will do.