Algaebra
posted by Taylor .
A rectangular swimming pool is 5 feet longer than it is wide. If a concrete walk 2 feet wide is placed around the pool, the area covered by the pool and the walk is 156 square feet greater than the area covered by the pool alone. What are the dimensions of the pool

First, draw a picture to represent the pool with walk around it.
Let x = width of pool, then x + 5 = length of pool
x+ 9 = length of walk, and x+4 = width of walk
Area of pool = x(x +5)
Area of walk and pool =(x + 9)(x + 4)
Area of pool + 156 = Area of walk and pool
x(x + 5) + 156 = (x + 9)(x + 4)
Now, solve the equation for x which wiki give you the width of the pool. 
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