Let T n be the number of all possible triangles formed by joining vertices of an n -sided regular polygon. If T n + 1 - T n = 10 , then the value of n is :

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Aicharya · Accepted Answer

Number of triangles = C 3 n Given: C 3 n + 1 - C 3 n = 10 &#8658; n 2 - n - 20 = 0 &#8658; n - 5 n + 4 = 0 &#8658; n = 5 , &#160; &#160; &#8757; n &#8800; 0

Let T n be the number of all possible triangles formed by joining vertices of an n -sided regular polygon.…

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