Answer:
D. (x,y)-->(3x, 3y)
Step-by-step explanation:
Look at the x-values first. To get from -3 to -9, subtract 6. to get from you subtract 6 or multiply by 3. To get from 2 to 6 you add 4 or multiply by 3. To get from -1 to -3 you subtract 2 or multiply by 3. The answer is multiply by 3.
Because D is the only answer that all x-values get multiplied by 3, D is correct.