Seudónimo Seudónimo 07-12-2020 Mathematics contestada consider the following system of equations x+y=11 2x+y= -3 which equation can be added to the system so the solution does not change PLEASE HELP ME!!! and the answer choices are: x-y=2 -2x+-2y=-2 3x+y=20 x+2y=18 please help 15 points for grabs