Question

(x2+y2-3xy) - (y2+3x2-4xy)​

Answer 1

Respuesta:

$-2x^2+xy$

Explicación paso a paso:

$\left(x^2+y^2-3xy\right)-\left(y^2+3x^2-4xy\right)\\=x^2+y^2-3xy-\left(y^2+3x^2-4xy\right)$

------------------------------------------------

$-\left(y^2+3x^2-4xy\right)\\=-\left(y^2\right)-\left(3x^2\right)-\left(-4xy\right)\\=-y^2-3x^2+4xy$

------------------------------------------------

$=x^2+y^2-3xy-y^2-3x^2+4xy\\=x^2-3x^2-3xy+4xy+y^2-y^2\\=-2x^2-3xy+4xy+y^2-y^2\\=-2x^2+xy+y^2-y^2\\=-2x^2+xy$