# given a^2 + n + 2b^2, find the value for n

#### tmelucero

##### New member
given a^2 + n + 2b^2
find the value for n

#### Loren

##### Senior Member
Re: help with this problem

Is there an equal sign some place? And, while you are at it, what have you done so far? Where are you having trouble?

#### tmelucero

##### New member
Re: help with this problem

I'm actually helping a friend who took a test and the given information was as follows

a^2+n+2b^2
and the factor of it is
(a+b)(a+2b)
so N=2ab right?

but it was a test and there were multiple choice answers and the answers were all fractions

#### tmelucero

##### New member
Re: help with this problem

the issue is all of the unknowns and no equal sign

#### Mrspi

##### Senior Member
Re: help with this problem

tmelucero said:
I'm actually helping a friend who took a test and the given information was as follows

a^2+n+2b^2
and the factor of it is
(a+b)(a+2b)
so N=2ab right?

but it was a test and there were multiple choice answers and the answers were all fractions
Let's see if I've got this right. You were given this expression:

a[sup:2tj27kjm]2[/sup:2tj27kjm] + n + 2b[sup:2tj27kjm]2[/sup:2tj27kjm]

You are told that the factors of this expression are (a + b) and (a + 2b).

If that's all correct, then you could multiply out (a + b)(a + 2b) to get

a[sup:2tj27kjm]2[/sup:2tj27kjm] + 2ab + ab + 2b[sup:2tj27kjm]2[/sup:2tj27kjm]
or,
a[sup:2tj27kjm]2[/sup:2tj27kjm] + 3ab + 2b[sup:2tj27kjm]2[/sup:2tj27kjm]

Comparing this with the original given trinomial, it sure looks to me like n = 3ab.

However, since it took two posts to get the information about the factors, I wonder if there is something ELSE important that we don't know yet.