Calculating Resistance and Power Dissipation in a Circuit

[cemar.]

1. There is a current of 0.25 A in the circuit of the figure
What is the value of the resistance R?

Hockay so. I know the change of voltage throughout the loop is 0.
therefore
0 = E1 - I(R1+R2) - E2 - 1R(unknown)
0 = 6V - 0.25A*18ohm - 12V - 0.25A*R
through algebra i get R=42.
And that's wrong. So i dontk now what I am doing wrong.

And it also asks for the power dissipated by R and i don't know whether to use the energy of both batteries or do a long equation with info from the whole circuit or what. I do know how ever that i should use the PR = IV or I^2R or (V^2/R)

thanks a bunch.

 

[cemar.]

okay I am technically challenged.
Take two on uploading this badboy.

 

[rock.freak667]

Attachments take long to approve. Upload the image on http://imagshack.us and use one of the links in it so that is shows up.

 

[cemar.]

okay got it thanks!
If you click on that link from the last guy who posted you get a really weird video of a chinese dog for anyone who is seriously easily amuzed or high.
http://img176.imageshack.us/img176/2045/knightfigure3150rg1.th.jpg