How many triangles and quadrilaterals altogether can be formed using the vertices of a 7-sided regular polygon?A. 35B. 40C. 50D. 65E. 70

Question

asked May 13, 2021 98.3k views

1 Answer

Victor Suzdalev · Answer 1 · 2021-05-17T17:59:09+0000

Answer:

E) 70

Explanation:

Using combination factorial

a triangle has three vertices and a quadrilateral has 4 vertices

The number of triangles and quadrilaterals = ⁷C₃ + ⁷C₄ =
(7!)/(4!3!) + (7!)/(4!3!) = 70