MathDB

Trig bash

Source: Excursion

June 25, 2020

trigonometrygeometrypentagonconvex quadrilateral

Problem Statement

Let

BCDK

be a convex quadrilateral such that

BC=BK

and

DC=DK

.

A

and

E

are points such that

ABCDE

is a convex pentagon such that

AB=BC

and

DE=DC

and

K

lies in the interior of the pentagon

ABCDE

. If

\angle ABC=120^{\circ}

and

\angle CDE=60^{\circ}

and

BD=2

then determine area of the pentagon

ABCDE

.

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