SOLUTION: This is subtracting rational expressions with the answer in factored form. I've been having trouble trying to figure this problem out. The r and x variables keep throwing me off wh

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: This is subtracting rational expressions with the answer in factored form. I've been having trouble trying to figure this problem out. The r and x variables keep throwing me off wh      Log On


   

Question 759696: This is subtracting rational expressions with the answer in factored form. I've been having trouble trying to figure this problem out. The r and x variables keep throwing me off when trying to subtract and find the common denominator. please help me
7x+3r..........................2x-r
______........----- _________
4xr^3 ........................x^2-r^2

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
7x+3r..........................2x-r
______........----- _________
4xr^3 ........................x^2-r^2
==========================================
Least common denominator: 4xr^3(x^2-r^2)
---------
[(7x+3r)(x^2-r^2) - (2x-r)(4xr^3]/lcd
----
= {[7x^3 -7r^2 + 3rx^2 -3r^3] - [8x^2r^3-4xr^4]}/ lcd
-----
There are no common terms in the numerator.
-----
= Repeat the last expression.
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Cheers,
Stan H.