Question

answer the attachment

Answer 1

$x + y = 3 \\ x = 0 \\ x + y = 3 \\ 0 + y = 3 \\ y = 3 \\ x - y = 1 \\ y = 1 \\ x - 1 = 1 \\ x = 1 + 1 \\ x = 2$
the coordinates of x+y = 3
x,y = 0, 3
the coordinates of x-y = 1
x,y = 2,1