1.

Find the number of diagonals of a polygon of 10 sides.

Answer» Assume that there are 10 points in a plane where no 3 of them are collinear which are the verticews of the given polygon,
The number of different lines that can be formed by joining these 10 points is `.^(10)C_(2)`.
We know in any polygon the lines joining non-adjacent vertices are called diagonals.
Hence, the required number of diagonals=Number of lines formed -Number of sides of the polygon `=.^(10)C_(2)-10=35`.
Using the formula, the number of diagonals in the above problem `=(10(10-3))/(2)=35`.


Discussion

No Comment Found

Related InterviewSolutions