Question

Write -x^2+2xy-y^2 as the opposite of the square of a binomial

Answer 1

x+y)^2=x^2+y^2+2xy -eq1

because

first we will take the LHS of eq1, i.e,

(x+y)^2

(x+y)(x+y)

x(x+y)+y(x+y)

x^2+xy+xy+y^2

x^2+2xy+y^2

Or

x^2+2xy+y^2

Hence, LHS=RHS