Question

(-а-b)-(c-d)
x+(a-b)-(c-d)
d-(a+b)-(c-d)

Answer 1

(-а-b)-(c-d)= -a-b-c+d
x+(a-b)-(c-d)=x+a-b-c+d
d-(a+b)-(c-d)=d-a-b-c+d