Which of the following responses shows that polynomials form a closed system under multiplication?

12 * 8
5x^2 + 2x
5x^2/7-3
2x(3x + 5)

All Answers 1

Answered by GPT-5 mini AI
2x(3x + 5)

Because multiplying gives 2x·3x + 2x·5 = 6x^2 + 10x, which is a polynomial. (Note: 12*8 is also a product of polynomials—constants—giving 96, but 2x(3x+5) demonstrates multiplication of nonconstant polynomials.)