Is there an algebraic formula to find out the area of a hexagon?

1 Answer
Jun 3, 2018

Depending upon what properties are known:

A = 3 a h A=3ah, or A = (3sqrt(3))/2 \ a^2

Explanation:

![https://www.shutterstock.com/image-vector/area-hexagon-279925802](useruploads.socratic.org)

Consider (as pictured:) a regular hexagon, with side length a. The regular hexagon is composed of 6 equilateral triangles, if we denote the height of one such triangle by h, the the area of a single triangle is:

A_T = 1/2 xx "base" xx "height
\ \ \ \ \ = 1/2 a h

Thus the area of the entire hexagon, is given by:

A = 6 A_T
\ \ = 6/2 a h
\ \ = 3 a h

If h is unknown, then we use pythagoras to get:

a^2 = h^2 + (a/2)^2
\ \ \ = h^2 + a^2/4

:. h^2 = (3a^2)/4

h = (sqrt(3)a)/2

Thus we can write:

A = (3) xx (a) xx ((sqrt(3)a)/2)
\ \ \ = (3sqrt(3))/2 \ a^2