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Does the following figure have rotational symmetry?
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If yes, find the angle of rotation.
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If a figure has rotational symmetry — imagine holding the shape down of the center, like a pivot point.
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And if the shape can turn, less than a full turn all the way back to the start, so if it can turn less than that and it looked the same or looked unchanged, it has rotational symmetry.
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And that shape does.
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Actually the turn that we’ve already drawn works.
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So here would be one example of rotational symmetry.
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Here is a second, turning it upside down.
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Here is a third.
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And if we were to draw a fourth one, it would be turning it all the way around a full 360 degrees back to the beginning.
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So we need to find the angle of rotation.
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An entire rotation all the way around is 360 degrees.
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And from our picture, we can see that it takes four different turns to get all the way back around.
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So in order to find the angle of rotation, we need to take 360 and divide by four.
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And we get 90 degrees.
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So this angle would be 90 degrees, and this one, and this one, and this one, making a full 360-degree circle.
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So does our figure have rotational symmetry?
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Yes, and the angle of rotation is 90 degrees.