Question

qual o valor da expressão (x-y)^2-(x+y)^2?

Answer 1

(x-y)² - (x+y)² =
x² -2xy+y² -x² - 2xy+y²
x²-x²-2xy-2xy-y²+y²
-2xy-2xy
-4xy

Answer 2

(x-y)²-(x+y)²
(x-y)*(x-y)-[(x+y)*(x+y)]
x²-xy-xy+y²-(x²+xy+xy+y²)
x²-xy-xy+y²-x²-xy-xy-y²
-4xy