



 
Hi Marie, I drew what you described and used $P$ to label the player. The area of the diamond is $90^2$ square feet and the area of the trapezoidal region formed by A, B, C and D is the area of the diamond minus the area of the triangle formed by first base, second base and the player. This is a right triangle with base length of $90$ feet and height $90  D$ feet. Write an expression for the area of the trapezoidal region and then differentiate it with respect to t. Evaluate this expression when $D = 22.5$ feet. Is the area increasing or decreasing when $D = 22.5$ feet? Penny  


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