What points do I graph the image of the rotation on?
1 answer:
Answer:
see attached
Step-by-step explanation:
No doubt you have seen that the tranformation that rotates a figure 270° CCW is the same as the one that rotates a figure 90° CW:
(x, y) ⇒ (y, -x)
This means the coordinate A(-3, 1) rotates to the position A'(1, 3). In this figure, that happens to coincide with point B.
When I drew this figure and the center of rotation O(0, 0), I was a little surprised to see the four points form a square. That makes it unsurprising that the point A gets rotated to point B by the desired transformation. (When you rotate a square 90° (or 270°) about one corner, an adjacent vertex (corner) will line up with the other adjacent vertex (corner).
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If you need to get a feel for rotations, so you can do this better in the future, it might be helpful to trace the figure (and the axes) onto a piece of tissue paper or tracing paper, then rotate it the necessary amount and see where the figure ends up.
This exercise may be easier with a print of the figure, but you can do it on a computer screen, too. (A touch screen makes it more difficult.)
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When a shape is rotated, it must be rotated through a point.
- <em>90 degrees counterclockwise rotation negates the y-coordinates, and then swap the x and y-coordinates</em>
- <em>Chanel is incorrect</em>
The rule of 90 degrees counterclockwise is:
This means that:
- <em>The y-coordinate is negated</em>
- <em>Then the y and x coordinates are swapped</em>
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However, Charlies transformation is incorrect.
- This is so because, the shape was not rotated, but instead it was reflected across the x-axis.
- Then, the shape was dilated
Using points L and Q
When L is reflected across the x-axis.
The rule is:
So, we have:
Next, it is dilated by 2.
The rule of this is:
So, we have:
From the diagram, the coordinate of Q is:
Same as the calculated point
Hence, Chanel is incorrect
Read more about transformation at: