Hello!
Since the second triangle is larger than the first this is an enlargement
To find the scale factor you find what the angles were multiplied by
(0 , 1) * 3 = (0 , 3)
(-1, -1) * 3 = (-3, -3)
(1, -1) * 3 = (3, -3)
So the scale factor is 3 since the coordinates were multiplied by 3
Hope this helps!