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How to do a 90 degree counterclockwise rotation?

User Nemec
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2 Answers

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Another way to do a 90 degree counterclockwise rotation is to use this rule: (x, y) to (-y, x).

So, you would take each coordinates of the figure and apply this rule.

For example, let's use (5, 7).

The rule is to take the x coordinate and put it on the other side of y, and y becomes negative.

(-7, 5) , and for that point you would plot in the new location in order to perform a 90 degree counter clockwise rotation.
User CFreitas
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First, you chose a point to rotate on. That point stays fixed and then you move the other side of the figure one quarter of a circle to the way that the clock does not go. That point should still be at the same place
User Altonymous
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