Question

Which is equivalent to the following expression?
(2x^2+4xy-y^2)+(x^2+3xy-y^2)

~3x^2-7xy-2y^2
~3x^4+7xy-2y^4
~3x^2+7xy-2y^2
~2x^2-7xy+2y^2

Answer 1

looks like it is \[3 x^2+7 x y-2 y^2\] hope that is one of the choices
http://www.wolframalpha.com/input/?i=%282x^2%2B4xy-y^2%29%2B%28x^2%2B3xy-y^2%29+

Answer 2

something is wrong with the question
you have \(2x^2\) and \(x^2\) which add up to \(3x^2\) and none of the choices has that
check the question again