There are two cordinates (x, y) but we also have a starting point and a derived/translated point; where D is the starting point and D' is the derived or translated point. We only need to manipulate the starting point cordinates to obtain the translated cordinates. In the starting coordinates we have Dx and Dy much like (x, y) where Dx is 7 and Dy is -3. And translated point we have D'x = 2 and D'y =5. The essence of this exercise is we manipulte the starting coordinates to obtain the translated coordinate while paying attention to the sign. So from Dx = 7, how do we obtain the translated D'x cordinates which is 2. We subtract 5 since 7-2 =5. Similarly from Dy = -3 how do we obtain the translated D'y coordinates which is 5. We add 8 since -3 +8 =5 . So our translation rule becomes (x-5, y+8)
