Using elimination to solve the system 2x + y = 8 and x + y = 4, which of the following could be the first step?
A2x + y = 8--------> 2x + y = 8
(x + y = 4)(-1)---> -x - y = -4
B2x + (4 - x) = 8
C2x + y = x + y
D3x + 2y = 12
Ex = 4
A2x + y = 8--------> 2x + y = 8
B2x + (4 - x) = 8
C2x + y = x + y
D3x + 2y = 12
Ex = 4