Answer:
D. Reflect across the y-axis and then across x = 7
Step-by-step explanation:
A and B work because each transformed point is 12 to the right (x-value is 12 greater), and 3 left then 15 right is the same thing as just 12 right.
C. works because if you take each of the points and reflect them over the y-axis (make the x value positive) and then across the line x=6 (vertical line at 6 on the x-axis) it will map the points onto the correct image.
So, the answer is D. Reflect across the y-axis and then across x = 7.
