From the figure, it can be seen that the mage A'B'C' is obtained from the pre-image ABC by translating/shifting the vertices of the image by 7 units to the right and 6 units down.
Therefore, the rule represents the translation from the pre-image, ΔABC, to the image, ΔA'B'C' is (x, y) → (x + 7, y – 6).
