Answer:
es 51.75
Step-by-step explanation:
por que al sumar 45 + 15 porciento da 51.75
y=19x+9 would be the rule
By definition we have to:
A set has under an operation if performance of that operation on set members always produces a member of the same set; in this case we also say that the set is closed under the operation.
For this case we have the following polynomials:

Multiplying we have:

The product of two polynomials is also a polynomial.
Answer:
d
is a polynomial
the first answer is correct