For this case we have the following system of equations: x - 4y = 1 x + 2y = 19 Using the elimination method we have: -4y - 2y = 1 - 19 -6y = -18 y = -18 / -6 y = 3 Then, by clearing x from any equation we have: x + 2y = 19 x = 19 - 2y x = 19 - 2 (3) x = 19 - 6 x = 13 The solution is given by: (x, y) = (13, 3) Answer: x = 13 option c.