The correct option is A 4x2+8y2−4x
Let the length of the rectangle =(3x2+4y2+4xy)
the breadth of the rectangle =(−x2−2x−4xy)
The perimeter of the rectangle =2(length + breadth)
So, the perimeter
=2[(3x2+4y2+4xy)+(−x2−2x−4xy)]
Grouping the like terms together, we get
=2[(3x2−x2)+(4xy−4xy)+(4y2)−2x]
=2(2x2+4y2−2x)
=4x2+8y2−4x