Question

Qual é a resposta:(3x+y)*(3x-y)

Answer 1

(3x+y)*(3x-y)

3x*(3x-y) + y*(3x-y)

=9x²-3xy+3xy-y² =9x²-y²

Answer 2

(3x+y)×(3x-y)
3x×3x-3x×y+3x×y-y×y
9x^2 - 3xy + 3xy - y^2
9x^2 - y^2