Which is true about the degree of the sum and difference of the polynomials 3x5y – 2x3y4 – 7xy3 and –8x5y + 2x3y4 + xy3?

Sum:

     3x^5*y - 2x^3*y^4 - 7x*y^3
 + -8x^5*y + 2x^3*y^4 +x*y^3

     -5x^5y - 6xy^3

Term 1: Degree = 6
Term 2: Degree = 4

Difference:

     3x^5*y - 2x^3*y^4 - 7x*y^3
 -  -8x^5*y + 2x^3*y^4 +x*y^3

     11x^5y - 4x^3*y^4 - 8xy^3

Term 1: Degree = 6
Term 2: Degree = 7
Term 3: Degree = 4

The degree of a term of a polynomial can be obtained by adding the exponents of the variables in that term.