Find the Area of a rectangle please help a pool 20 ft by 30 ft is going to have a deck x feet wide added all the way around the pool write an expression in simplified form for the area of the deck. I have tried doing this but have failed please help

You are on the correct path cris. 
The pool is still a rectangle, even with the new deck.  Thus you are almost correct.  
Each side will have $x$ feet added to it. 
Thus it will be $(20+2x)(30+2x) = 4x^2+100x+600$
Try finding the answer to this: 
If there is only 120 Feet of bamboo for the new deck,what is the largest the new area (pool + deck) can be. 
