Which of the following shows that polynomials are closed under addition when two polynomials 4x2 − 8x − 7 and −5x + 16 are added?

4x2 − 13x + 9 may or may not be a polynomial

4x2 + 13x − 23 may or may not be a polynomial

4x2 − 13x + 9 will be a polynomial

4x2 + 13x − 23 will be a polynomial

Question

Which of the following shows that polynomials are closed under addition when two polynomials 4x2 − 8x − 7 and −5x + 16 are added?

 4x2 − 13x + 9 may or may not be a polynomial

 4x2 + 13x − 23 may or may not be a polynomial

 4x2 − 13x + 9 will be a polynomial

 4x2 + 13x − 23 will be a polynomial

anonymous · Answer

@phi @Hero @iambatman

hero · Answer

Which do you believe is correct?

hero · Answer

Have you added the polynomials together yet?

anonymous · Answer

no, i dont know what the question means

anonymous · Answer

Ok, I added the two together and got 4x^2-13x*9  (?) oh and sorry for the late reply

anonymous · Answer

@Hero @Whitemonsterbunny17

hero · Answer

Is 4x^3 - 13x + 9 a polynomial?

anonymous · Answer

yeah, i think ?

hero · Answer

Yes, it's a polynomial. If you're not 100% certain about it, look up the definition of a polynomial. In the mean time, it should be obvious what the answer is at this point.

anonymous · Answer

ok, great! thanks!