(x^2+y^2)^2+2x^2y^2-y^4=x^2(x^2+4y^2)
Step-by-step instructions please, thank you!
you have x^4+2x^2y^2+y^4+2x^2y^2-y^4 on the left side, which makes x^4+4x^2y^2. on right side, it is x^4+4x^2y^2. these are both equal.
HOPE THIS HELPED!
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