since I don't have any data about the coordinates, I am simply calling them xj, yj, and xj' and yj'.
J = (xj, yj)
K = (xk, yk)
L = = (xl, yl)
a translation (shift) 2 units to the left just means, that the y coordinates regain the same, but the x coordinates are decreased ("to the left" = getting smaller) by 2.
