The answer would be B, (7,-1) because of what happens when you plug in the numbers. For the first equation, 2x+4y=10 would become 2(7)+4(-1)=10 which turns into 10=10 resulting in a true statement. For the next one, -2x+y=-15 which becomes -2(7)+(-1)=-15 which results in -15=-15 meaning B is the true answer for both equations
