Post a New Question


posted by .

What is the area of a regular pentagon with a side length of 9.4 feet and an apothem length of 6.5 feet?

  • Geometry -

    asume 11 and 12 are parallel 5 is 83 what is the measure of 7

  • Geometry -

    no sides of a regular pentagon are parallel
    5 is not 83
    7 is 7

    What planet are you calling from?

    Divide the pentagon into 5 congruent triangles with base angles of 54°

    If s = side length,
    the triangles have base = s
    then the apothem is h = s/2 tan 54°

    The area of the pentagon is 5 * s/2 * s/2 tan 54° = 5s^2*tan54°/4

    Note that this is just area = 1/2 * perimeter * apothem

    Note: 6.5/4.7 = 1.383 but tan54° = 1.376 so the above dimensions do not fit a regular pentagon.

    Ignoring that, however, and using their figures,

    a = 5*9.4/2 * 6.5 = 152.75

  • Geometry -

    Erica is playing with some regular pentagon tiles and discovers she can made a five pointed star:Explain how she can use angle measures of the pentagons to fink the angle measure of the point of the star

Answer This Question

First Name:
School Subject:

Related Questions

More Related Questions

Post a New Question