Respuesta :

Answer:

  9x² -6xy +y²

Step-by-step explanation:

The square of the binomial can be written directly using the relationship ...

  (a +b)² = a² +2ab +b²

where you have a=3x and b=-y.

  area = (3x -y)² = (3x)² + 2(3x)(-y) + (-y)²

  area = 9x² -6xy +y²