Question

Choose the correct simplification and demonstration of the closure property given: (2x3 + x2 − 4x) − (9x3 − 3x2).

−7x3 + 4x2 − 4x; may or may not be a polynomial
−7x3 + 4x2 − 4x; is a polynomial
11x3 − 2x2 − 4x; may or may not be a polynomial
11x3 − 2x2 − 4x; is a polynomial

Answer 1

−7x3 + 4x2 − 4x; is a polynomial

Explanation:

Got it right in my test.

Answer 2

B)

Explanation:

(2x^3+x^2-4x)-(9x^3-3x^2)

2x^3-9x^3+x^2-(-3x^2)-4x

-7x^3+x^2+3x^2-4x

-7x^3+4x^2-4x