Question

The equation D=žn(n-3) gives the number of diagonals D for a polygon with n sides. Use this equation to find the number of diagonals for a palygon that has 6 sides.

Answer 1

`9`

1) Considering that the formula for the number of diagonals of a polygon is:

`D=(n(n-3))/(2)`

2) And the question tells us that we need to find the number of diagonals for a polygon that has 6 sides, we can plug into that n=6 and solve it this way:

`\begin{gathered} D=(6(6-3))/(2) \\ D=(6\left(3\right))/(2)=(18)/(2) \\ D=9 \end{gathered}`