# How to expand this polynomial division?

My Physics teacher gave me a problem and its solution, what I have todo is to expand the solution, but when I do it I do not get to the same solution he says is the right one, here is the problem:

We cut off a rectangle ABCD along the line DE through the corner D, so when we suspend the plate ABED from the point E the line DA, is on horizontal position. Calculate the magnitude EB The image below is the solution, What I am not able to figure out is how the teacher solved the polynomial division and get to that result. Any help is appreciated

• Try multiplying each term in the numerator and denominator by $6/h$, then simplifying the denominator. – N. F. Taussig Sep 7 '14 at 20:03
• @N.F.Taussig Another question, how did you know that? – Victor Castillo Torres Sep 7 '14 at 20:20
• @N.F.Taussig How, did you get to that? please answer – Victor Castillo Torres Sep 7 '14 at 21:37

## 1 Answer

You do not need to do polynomial division • Yeah, I know, But I have to put all the process from ah(h/2) till 3a^2 - (a-x)^2. – Victor Castillo Torres Sep 7 '14 at 22:31
• Oh, ok; I thought you were just having trouble with getting his final answer. So for that step you can just factor an h out of both terms in the numerator and both in the denominator, so h/h will cancel, then multiply top and bottom by 2 and by 3 (or 6) to get rid of the fractions. – daveB Sep 8 '14 at 5:24