We have:
Then we use trigonometric identities to change the negative sign of the trigonometric functions, so:
We clear f(x):
we simply what we can:
Thus, the correct answer is;
If P = (-1,-1), find the image
1 answer:
<h3>Answer: (-1, 1)</h3>
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Explanation:
The rotation rule we use is
The x and y coordinates step places, then the second coordinate (after the swap) changes in sign from positive to negative, or vice versa.
For example, the point (5,7) rotates to (7, -5). As another example, (2,-1) becomes (-1, -2). As another example, (-9,4) becomes (4,9).
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In our case, the point (-1,-1) will rotate to (-1, 1)
Note: A 270 degree counterclockwise rotation about the origin is the same as a 90 degree clockwise rotation about the origin. Refer to the diagram below.
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The given line is:
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So, a line perpendicular to the one given is of the form:
We substitute the given point to find "b":
Finally we have:
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ANswer: