<-- a
<-- b
<-- c
<-- d
<-- angle 1 α
<-- angle 2 γ
  

The following practice problem has been generated for you:
Given a quadrilateral with sides a = 14, b = 14, c = 4, and d = 4 with opposite angles α = 47 and γ = 47, calculate the area using Bretschneider's formula