Answer :
Answer:
A. The coefficients of the sum are whole numbers and the sum is a polynomial.
Step-by-step explanation:
The approach to demonstrate the closure property for the sum consists in defining what a polynomial is and demonstrate that the sum of two polynomials with integer coefficients is equal to a polynomial with integer coefficients. We proceed to show the proof below:
1) [tex]5\cdot m -3[/tex], [tex]2\cdot m + 4[/tex] Given
2) [tex](5\cdot m -3)+(2\cdot m +4)[/tex] Definition of addition
3) [tex](5\cdot m +2\cdot m ) +[(-3)+4][/tex] Definition of substraction/Associative and Commutative properties
4) [tex](5+2)\cdot m +1[/tex] Distributive property/Definition of substraction
5) [tex]7\cdot m +1[/tex] Definition of addition/Result
Hence, the coefficients of the sum are whole numbers and the sum is a polynomial. The correct answer is A.