Draw a polygon on the floor, using a piece of chalk.
(In the
figure, a pentagon ABCDE is shown) (Fig 3.8).
We
want to know the total measure of angles, i.e,
along AB. On reaching B, you need to turn through an
angle of mZ1, to walk along BC. When you reach at C,
you need to turn through an angle of m/2 to walk along
CD. You continue to move in this manner, until you return
to side AB. You would have in fact made one complete turn.
Therefore, m/1+m/2+m/3+m/4+mZ5 = 360°
This is true whatever be the number of sides of the polygon.
m21+mZ2+mZ3+mZ4+mZ5. Start at A. Walk
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