The shaded area represents a cement walkway around a pool. state the algebraic expression that represents the difference between the outside perimeter of the walkway and the perimeter of the pool.

Andy wants to find the distance d across a river. he located points as shown in the figure, then use similar triangles to find that d = 223.5 feet. how can you tell without calculating that he must be wrong? tell what you think he did wrong and correct his error. round your answer to the nearest tenth if necessary. andy must have used the wrong . the distance d is actually feet.