That's not possible.
The difference between the question the way it's printed in the book and the way
you gave it to us is that little word "shown". In the book, it directs your attention
toward the picture beside it, but here it doesn't. Without the picture, we don't even
know how many sides the polygon has, so we don't know what the angles add up to.
Any clever trick that we might want to use to answer this problem won't work.
We either need to see the picture, or else you have to give us a good description
of what's in it.
