Final answer:
The scale factor of the dilation from triangle qrs to triangle q'r's' is calculated by dividing the length of line q'r' by the length of line qr, which results in a scale factor of 3.
Step-by-step explanation:
The student is asking about the scale factor of a dilation in geometry, specifically for triangle q'r's' which is a dilation of triangle qrs. To find the scale factor, you can compare the lengths of corresponding sides in the pre-image and the image. In this case, the length of line qr is 3 and the length of line q'r' is 9.
To calculate the scale factor, you divide the length of a side in the image (q'r') by the length of the corresponding side in the pre-image (qr). So the scale factor would be q'r'/qr = 9/3 = 3. Therefore, the scale factor of the dilation is 3.