if polygon MAST with coordinates M (-3, -1), A (-3, 2), S (-1, 3), and T (1,1) is
if polygon MAST with coordinates M (-3, -1), A (-3, 2), S (-1, 3), and T (1,1) is reflected across x = -3, then which of the following coordinates represent the vertices of the polygon M'A'S'T'?