<h3>Answer: Choice C</h3>
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Explanation:
The x coordinate of the preimage point Q is x = 6.
The x coordinate of the image point Q' is x = 21.
The ratio of image over preimage is 21/6 = (3*7)/(3*2) = 7/2
You'll get this same value if you do the same steps with the y coordinates.
Therefore, the scale factor is 7/2 and the dilation rule is
Note: 7/2 = 3.5