Which of the following polynomials corresponds to the product of the multivariate polynomials 4x - 3y + 5 and x + 2y - -3?

If the second polynomial is x + 2y -3, we multiply
    (4x - 3y + 5) (x + 2y - 3)

We distribute each term of the first polynomial (4x - 3y + 5) to every term

of the second polynomial (x + 2y - 3):   
    (4x - 3y + 5) (x + 2y - 3) = 4x^2 + 8xy - 12x
                                                       - 3xy          - 6y^2 +   9y
                                                                +  5x            + 10y - 15

Then combine similar terms:
    (4x - 3y + 5) (x + 2y - 3) = 4x^2 - 6y^2 + 5xy - 7x + 19y - 15

If the second polynomial is x + 2y --3, we multiply
    (4x - 3y + 5) (x + 2y + 3) = 4x^2 + 8xy + 12x
                                                        - 3xy          - 6y^2 -   9y
                                                                  +  5x          + 10y + 15

    (4x - 3y + 5) (x + 2y - 3) = 4x^2 - 6y^2 + 5xy + 17x + y + 15

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