Did I do this right ??

yes you did

Step-by-step explanation:

Yes.

Step-by-step explanation:

You can check corresponding points on the 2 triangles by the distances along the x axis  and y axis you have to move from the origin.

For example, take  the highest points on the triangles:

For the small triangle to get to this point you move 2 from the origin to the right and up 4.

On the large one we move 4 to the left and 8 up, which is twice the distance. So the scale factor is 2.