What is true about the sum of the two polynomials? 6s2t – 2st2

4s2t – 3st2

The sum is a binomial with a degree of 2.
The sum is a binomial with a degree of 3.
The sum is a trinomial with a degree of 2.
The sum is a trinomial with a degree of 3.

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  The sum is a binomial with a degree of 3.

Step-by-step explanation:

The sum is ...

  (6s²t -2st²) +(4s²t -3st²) = s²t(6 +4) +st²(-2 -3)

  = 10s²t -5st² . . . . . . . a binomial of degree 3

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The degree of the polynomial is the maximum sum of the degrees of the variables in each term. The first term is degree 2+1 = 3; the second term is of degree 1+2 = 3. The degree of the binomial is 3.