Select the correct answer from each drop-down menu. A system of equations and its solution are given below. System A x - y = 7 -3x + 9y = -39 Solution: (4,-3) Complete the sentences to explain what steps were followed to obtain the system of equations below. System B x - y = 7 6y = -18 To get system B, the equation in system A was replaced by the sum of that equation and times the equation. The solution to system B the same as the solution to system A.