factor the expression 81x^2-54xy+9y^2 into product of binominials

Answer 1

81x^2 - 54xy + 9y^2
9(9x^2 - 6xy + y^2)
9(3x - y)(3x - y)
9(3x - y)^2

Answer 2

I am very careful

Answer 3

81x^2-54xy+9y