Math Word problem with factoring...HELP!!! This questions has me stumped!? I have been working on it for days...

Question

A 10ft-by-15ft pool was installed in your backyard. You have $3000 left that you would like to spend on surrounding the pool with a patio, equally wide on all sides. Write an expression in terms of x for the length and width of the patio.

1.Find the area of the swimming pool

2.Write an algebraic expression for the total area of the region containing both the pool and the patio

3.Use subtraction to find an algebraic expression for the area of just the patio.

4.Find the perimeter of the swimming pool alone.

5.For each patio material option, write an algebraic expression for the total cost of installing the patio based o its area and the given price information.
a) poured cement $5.00 per square foot
b) Bricks $7.50 per squre foot pluse a $30 flat fee for delivering
c)Outdoor carpeting $4.50 per squre foot plus $10.86 per foot of the pool's perimeter to install edging

6. If you plan to speed the entire $3000 on the patio, how wide would the patio in option A be?

7.If you plan to speed the entire $3000 on the patio, how wide would the patio in option B be?

8.If you plan to speed the entire $3000 on the patio, how wide would the patio in option C be?

9.Which option wou choose?What are some of the pros and cons for each options?

Answer 1

length= 15+x
width=10+x

total area of just patio= (15+x)(10+x)-10*15

perimeter spool= 2*10+2*15

Answer 2

6. $45
7. $55
8.65