The question is incomplete.
The complete question is:
Given the functions j(x) = x² − 9 and k(x) = −x + 7, which operation results in a 3rd degree polynomial?
Answer: the multiplication of j(x) and k(x)
Explanation:
1) j(x) × k(x) = (x² − 9) ( − x + 7)
2) Use distributive propery:
(x²)(- x) + (x²) (7) + (-9)(-x) + (− 9) ( 7) = - x³ + 7x² + 9x - 63
The exponent of x is 3, hence this is a third degree polynomial.
