Answer:
Scale factor = -5
Explanation:
Dilation is a transformation that resizes a figure by a scale factor, causing all distances from the center of dilation to be multiplied by the same factor.
The coordinates of the preimage vertex are (3, -5).
The coordinates of the image vertex are (-15, 25).
In this case, the center of dilation is the origin (0, 0). Therefore, we can find the scale factor (k) by dividing the x- and y-coordinates of the image by the corresponding x- and y-coordinates of the preimage:


Since the scale factor is the same for both x and y, we can say that the scale factor of the dilation is k = -5.
Note that when the scale factor in a dilation is negative, it indicates that the dilation takes place in the opposite direction from the center of dilation on the same straight line containing the center and the pre-image point.