April 21, 2014

Homework Help: Algebra

Posted by Sara on Friday, July 20, 2007 at 10:53am.

Posted by Tammy on Thursday, July 19, 2007 at 10:12pm.
download mp3 free instrumental remix
--------------------------- Divide top by bottom

Very Big Problem and help would be greatly appreciated

For Further Reading

Algebra - Reiny, Thursday, July 19, 2007 at 11:59pm
not that tough once you notice that your question has the pattern
(a/b + b/a)(b/a - a/b)
where a = 3x+4 and b=3x-4

this easily reduces to (a^2 + b^2)/(b^2 - a^2)

now replace a and b with 3x+4 and 3x-4 and it simplifies to


hmm, the answer is right (it's in my book) but I don't understand how you simply reduce it to (a^2+b^2) (b^2-a^2)
and from there when I tried to replace a and b with 3x+4 and 3x-4 I don't know how to simplify it or get the answer. Could you write down the steps detailed? I have a bunch of problems that I can't solve that are similar, so I think if I understand the concept of this one I will be able to sove all the other ones.

The fact that there was that nice symmetry to the question, makes it easier than it first appears.

I had it as:

(a/b + b/a)(b/a - a/b)

look at (a/b + b/a)

the common denominator for this would be ab, so
a/b + b/a = (a^2 + b^2)/ab

similarly for

(b/a - a/b) the common denominator is ab and this reduces to
(b^2 - a^2)/ab

so now we have
(a^2 + b^2)/ab (b^2 - a^2)/ab

remember when dividing one fraction by another, we multiply by the reciprocal of the second fraction, so

(a^2 + b^2)/ab (b^2 - a^2)/ab

=(a^2 + b^2)/ab * ab/((b^2 - a^2)

the ab's cancel and that's how I got

(a^2 + b^2)/(b^2 - a^2)

Now replace the original values of a and b and you should be able to do that yourself.

Answer this Question

First Name:
School Subject:

Related Questions

Algebra - (3x+4)/(3x-4)+(3x-4)/(3x+4) --------------------------- Divide top by ...
calculus - I am trying to find equation of the tangent line to the curve 2/(1-3x...
Algebra.. - Check These Answers Please? f(x)= x^2+3 ; g(x)=3x-1 1. (f+g) =x^2+3x...
Algebra - How would I complete this problem? Geometry. The area of a rectangle ...
Reasons in Proof - *I KNow only #6 which is relfexive,I think...You have to find...
algebra - Solve for x. (l is the absoulte bar, not one) 3*l 3x-2 l -6 > l 3x-...
Algebra - What is the equation of the line that passes through point (7,-2) and ...
algebra - Solve the system by graphing. 3x+y=6 3x-y=0 I'm kind of unsure about ...
PRoof reasons in Algebra - Statements Reasons 1. 3x - 7 = -4 1. 2. 3x - 7 + 7...
Math (Calculus AB) - An equation to the graph of y=x^3+3x^2+2 at its point of ...