x+y±5=0x+y \pm 5=0x+y±5=0
x+y±25=0x+y \pm 2 \sqrt{5}=0x+y±25=0
2x−y±10=02 x-y \pm 10=02x−y±10=0
x−y±10=0x-y \pm 10=0x−y±10=0