We want to know the mistake is doing Andrew when he tries to draw a copy of ∆ABC using the vector v.
We see that the vector v is directed 3 units to the right, and 3 units down.
For translating the triangle ABC with the vector v, we should make the translation with every point of the triangle.
This means that you move the point A 3 units down and 3 units to the right, but Andrew just moved it 2 units down, and 3 units to the left. Also, we have:
0. The point B was moved two units down and four units to the right.
,1. The point C was moved three units down, and three units to the right
Thus, Andrew didn't move correctly the points A and B.