Hello! I need help with this linear map problem. Thank you in advance..!

Let T(x, y) = (ax + by, x - y). Find a, b E R such that T(x, y) maps the square with vertices (0, 0), (0, 2), (2, 0), and (2, 2) to a quadrangle such that three vertices of the quadrangle are (0, 0), (0, 2), (1, 0) and the fourth one is an arbitrary point