Answer:
reggie made an error
the correct scale factor is 2/3
Explanation:
we want to get from A to A', B to B', and ultimately C to C'
to get there, we must multiply each value in each point by the scale factor.
let's start out with reggie's scale factor. he multiplies each value in C by 3/2 to get to C'. we can try this out with one point, e.g. A
for A: 3/2 * (-12, -6) = (-18, -9). this is not A' = (-8, -4)! thus, 3/2 cannot be the scale factor
now, onto hillary's scale factor of 2/3
for A: 2/3 * (-12, -6) = (-8, -4). this is A'! thus, hillary is correct and reggie made an error
the correct scale factor is thus hillary's: 2/3