## Elementary Geometry for College Students (6th Edition)

The measure of the reflex angle at vertex E is $~216^{\circ}$
We can find the value of $x$ by considering the sum of all five interior angles: $x+x+2x+2x+4x = (5-2)~\cdot 180^{\circ}$ $10x = (3)~\cdot 180^{\circ}$ $x = 54^{\circ}$ We can find the measure of the reflex angle: $4x = (4) \cdot (54^{\circ}) = 216^{\circ}$