Can someone explain this for me : ) when you multiply a difference of two squares, why is your answer a binomial instead of a trinomial like when you multiply the sum of two squares?

Difference of two squares: (a+b)(a-b) = a² - b²(a-b)(a+b) = a² - b²the difference of two squares results to a binomial because the middle term cancels each other out.example: a = 2 ; b = 3(2 - 3)(2 + 3) = 2(2+3)-3(2+3) = 4+6-6+9 = 4 + 0 + 9 = 4 + 9