Question

what should be subtracted from 5x²- 6y²+7xy+19 to obtain 3x²-2y² + 4xy +13 ​

Answer 1

Let the number be x

So

(5x^2-6y^2+7xy+19)-x=3x^2-2y^2+4xy+31

(5x^2-6y^2+7xy+19)-(3x^2-2y^2+4xy+31)

=x

5x^2-6y^2+7xy+19-3x^2-2y^2+4xy+31=x

2x^2-8y^2+11xy+50=x