The side of an nonagon is 12. Calculate perimeter, area

P = 9 x side

P = 9 x 12

P =

A = 9/4s

A = 9/4(12)

A = 9/4(144)cot(20)

A = 324 x 2.4

A =

Interior Angle Sum = (sides - 2) x 180°

Interior Angle Sum = (9 - 2) x 180°

Interior Angle Sum = 7 x 180°

Interior Angle sum = 1260°

Diagonals = | n(n - 3) |

2 |

Diagonals = | 9(9 - 3) |

2 |

Diagonals = | 9(6) |

2 |

Diagonals = | 54 |

2 |

Diagonals =

1 vertex Diagonals = n - 3

1 vertex Diagonals = 9 - 3

1 vertex Diagonals =

Triangles = N - 2

Triangles = 9 - 2

Triangles =