P=2I+2W to solve this equation for W you do whatever you need to to isolate W so
subtract 2I form both sides: P-2I=2W since 2I-2I=0
the divide both sides by2 :(P/2)-I=W and there you have it w=(P/2)-I now you can put the numerical values for P and I in this equation and calculate a value for W.
Hope this helps
Jim
Alex C.
03/17/16