How many triangles can be formed from non collinear points?
Hint: In general the number of ways to select r thing n number of things is $ ^{n}{{C}_{r}} $ .
We can define $ ^{n}{{C}_{r}} $ as below: $ ^{n}{{C}_{r}}=\dfrac{n!}{r!\times (n-r)!} $ Complete step-by-step answer: Show Note:To draw a triangle we need three points. But we cannot draw a triangle from three collinear points.
How many nonHence, these points A, B, C, D, E, F are called non - collinear points. If we join three non - collinear points L, M and N lie on the plane of paper, then we will get a closed figure bounded by three line segments LM, MN and NL. This closed figure is called a Triangle.
How many triangles can 4 nonStep-by-step explanation:
4 non colinear points define C(4, 2) = 3*4/2 = 6 straight lines. 6 lines, if they were random, they would define C(6, 3) = 4*5*6/1*2*3 = 20 triangles.
How many triangles form 12 nonHence the answer is C(11,2).
How many triangles can you make using nonTo form a triangle we require 3 non-collinear points. As we have 6 non-collinear points, we have to choose 3 out of 6. We can, therefore, make 20 triangles from 6 non-collinear points.
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