Question

How many triangles can be obtained from 5 points in a plane? (no 3 points are collinear). select one:?

Answer 1

I am telling you about with the 6 points.

 The six points simply existing in three dimensional space can still form the 20 triangles as surmised by the two previous answers, assuming no three are collinear.  Any three non-collinear points must be in the same plane, thus forming the vertices of the triangle.

You do not give out information about whether there is any degree of col-linearity between the six points and so, I will assume they are non-colinear. Then it just amounts to the number of ways you select the three vertices. Which is just (6/3)

Answer 2

Answer: There are 10 triangles that can be obtained from 5 points in a plane.

Step-by-step explanation:

Since we have given that

Number of points are there = 5

We need to obtain a triangle.

Number of points needed for triangle = 3

So, we will use "Combination ":

here, n = 5

r = 3

So, it becomes,

$^5C_3=\frac{5!}{3!\times 2!}\\\\^5C_3=10$

Hence, there are 10 triangles that can be obtained from 5 points in a plane.