Resultant forces question

The two forces are 2n+1 and n^2+n. They're on a right angle. No idea what to do

Draw a triangle of the forces. Since they're at a right-angle then the resultant force is simply some Pythagoras' Theorem application.

It says the answer has to be a number. :/

Then I don't understand the question unless you didn't post all of it. Take a pic of it and post it here.

Sorry my mistake, I don't need the answer in numbers. It was just the next questions first line and I thought it was the last line of this question...

Anyways I've done some pythagoras but I'm not sure if it's okay to leave my answer in this form (also not sure if my answer is correct).
a^2 = b^2 + c^2
=(2n+1)^2 + (n^2+n)^2
=4n^2 + 4n + 1 + n^4 + 2n^3 + n^2
=n^4 + 2n^3 + 5n^2 + 4n + 1
Then
a = sqrt(n^4 + 2n^3 + 5n^2 + 4n + 1)

We haven't done any fourth degree polynomial factorisation yet so I'm not really sure what to do with my answer.

It doesn't factorise so I'd leave it as that.

Sorry my mistake, I don't need the answer in numbers. It was just the next questions first line and I thought it was the last line of this question...

Anyways I've done some pythagoras but I'm not sure if it's okay to leave my answer in this form (also not sure if my answer is correct).
a^2 = b^2 + c^2
=(2n+1)^2 + (n^2+n)^2
=4n^2 + 4n + 1 + n^4 + 2n^3 + n^2
=n^4 + 2n^3 + 5n^2 + 4n + 1
Then
a = sqrt(n^4 + 2n^3 + 5n^2 + 4n + 1)

We haven't done any fourth degree polynomial factorisation yet so I'm not really sure what to do with my answer.

Have you definitely posted the whole question? It just seems a bit strange.

This is the whole question sorry for the terrible quality and size

Okay if that's the actual question then the answer you gave earlier is correct, as RDKGames confirmed.

Was it a textbook question?

Nope, it was on a sheet given to us by a teacher. Looked hand drawn, but she collected them back in.