Question

Sophia is dilating a figure. one of her pre-image points with coordinates (-3, 5) has an image with coordinates (-9, 15). If one of the other image points has coordinates (3, 1), what are the coordinates of its pre-image point?
A. (9, 3)
B. (1, 1/3)
C. (1,3)
D. (-3,-1)

Answer 1

(9,3) I believe. Because to get from -3 to -9 you multiply by three, as well as 5 to 15. So you simply multiply multiply these coordinates by three. 

Answer 2

Answer:

(1, 1/3)

> To get from (-3, 5) to (-9, 15) you do x3 to x & y

> 3 is the scale factor

> To figure out the pre-image point, you divide x & y by 3

> Therefore, (1, 1/3) is the answer