Parallel and Series Resistor Simplification

Hi,

I need help simplifying this circuit with parallel and series resistors. I am mainly confused, because there seems to be a point in my simplification where in picture 4 and 5 of my second image where the remaining 3 resistors are connected by 1 node.

I tried to simplify them as resistors in parallel, but I end up with the wrong answer, and this doesn't seem like the correct thing to do.

Homework Statement

The Resistor equivalent of the entire circuit is 9 ohms. And the answer for 'R' is 15 ohms. However I do not know how to obtain this answer.

Homework Equations

Series Resistors = R1 + R2 = Rtotal
Parallel = R2*R1/R1+R2 = Rtotal
= 1/R3 + 1/R2 + 1/R1 = Rtotal

The Attempt at a Solution

Here are the images of my attempted solutions:

image 1 (the problem):
http://img22.imageshack.us/img22/9206/resistor1.jpg [Broken]

image 2 (my analysis):
http://img22.imageshack.us/img22/4978/resistor2.jpg [Broken]

Any help would be appreciated.

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