Question

[(x+y).(x-y)]+[(x-y).4] = ?

Answer 1

[(x+y).(x-y)]+[(x-y).4] = ?
[(x + y)(x - y)] + [ ( x - y)4]
[(x² - xy + xy - y²)] + [ 4x - 4y]
[(x²         0     - y²)] + [  4x - 4y]

x² - y² + 4x - 4y

Answer 2

x² - xy +xy - y²  + 4x-4y
x²-y²+4x - 4y