Question

[phamthiminhtrang]

600 + 500 = 1800 + x

Answer 1

[hoathien cot]

600+500=1800+x

1100       =1800+x

=>1800+x=1100

    x          =1800-1100

    x          =700

Answer 2

[Nguyễn Đình Phong]

x+1800=600+500

x+1800=1100

x=1100-1800

x=(-700)