Is my answer right?

$\displaystyle (3x^3&-5x^4&-10x&+1)&+(17x^4&-x^3)$

$\displaystyle (3x^3&-5x^4&-10x&+1)$

+$\displaystyle (17x^4&-x^3)$

Answer =$\displaystyle 12x^4&-x^3&-10x&+1$

I was told it does not have to be in standard form, but it helps to have it in standard form.. Is that true?