Question

x 2 + y2 –( -y 2 + 3x2 -4xy)

Answer 1

Step-by-step explanation:

X2 + y2 - (-y2 +6 -4xy)

X2 +y2 +y2 - 6 +4xy

x2 +2y 2 +4xy - 6

Answer 2

Given,

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

$=-(y^2+3.2-4xy)\\=y^2-6+4xy\\=x^2-y^2-y^2-6+4xy\\=x^2-2y^2-6-4xy$