Question

ΔRST is dilated about the origin, O, to create ΔR'S'T'. Point R is located at (3, 9), and point R' is located at (1.2, 3.6). Which scale factor was used to perform the dilation?

Answer 1

solve the following equation for k

3k = 1.2

Answer 2

the idea is that the scale factor, call it k, multiplies with each coordinate to get a new coordinate

so you multiply x = 3 with k to get the new x coordinate of x = 1.2

That's why 3k = 1.2

Answer 3

The same can be said with the y coordinates

solving 9k = 3.6 will give you the same k value